RELAXIN ANALOGS AND METHODS OF USING THE SAME

[0001] The disclosure relates generally to biology and medicine, and more particularly it relates to relaxin (RLN) analogs, especially long-acting, single-chain RLN analogs that can bind to a RLN/insulin-like family peptide (RXFP) receptor, such as the RXFP1 receptor, thereby functioning as RXFP receptor agonists. The disclosure further relates to compositions including the same and their use in treating cardiovascular, pulmonary and/or renal conditions, diseases or disorders.

[0002] Relaxins (RLNs) are part of the insulin superfamily and, in humans, include seven peptides of high structural, but low sequence, similarity– RLN1 (H1RLX, RLXH1 or H1), RLN2 (H2RLX, RLXH2 or H2), RLN3 (RXN3, ZINS4 or H3), insulin-like (INSL) peptide 3 (INSL3), INSL4, INSL5 and INSL6. Of particular interest herein is RLN2, which is a heterodimer of two peptide chains of twenty-four and twenty-nine amino acids (A chain and B chain), respectively, linked by two disulfide bonds with the A chain further having one intramolecular disulfide bond (see, Schwabe & McDonald (1977) Science 197:914-915). RLN2 is produced from its prohormone, prorelaxin, by cleaving a C peptide therefrom.

[0003] Physiologically, RLN2 exhibits a diverse array of functions that modulate cardiovascular, hepatic, neural, pancreatic, pulmonary and renal adaptations such as vasodilatory, anti-fibrotic and angiogenic effects, even though it initially was described as a pregnancy hormone. RLN2 signaling occurs through two different classes of G-protein-coupled receptors (GPCRs), namely, leucine-rich repeat-containing GPCRs LGR7 and LGR8, now referred to as the RXFP1 and RXFP2 receptors, respectively. Two other receptors in this family include the RXFP3 and RXFP4 receptors. RLN2 has a short half-life (t½), which presents challenges when using it as a therapeutic agent. In fact, native RLN2 has a t½ of minutes in vivo. Consequently, clinicians administer RLN2 by continuous intravenous infusion, which often results in inconvenience for individuals receiving the RLN compound and in short-term efficacy.

[0004] A number of RLN2 analogs exist having an improved t½. For example, Intl. Patent Application Publication No. WO 2018/148419 describes analogs that include a non-native amino acid residue such as para-acetyl-phenylalanine to which linkers, polymers and/or pharmacokinetic enhancers can be attached to improve t½. Intl. Patent Application Publication No. WO 2018/138170 describes analogs that are fusions of the A chain and B chain having a linker of at least fifteen amino acids and a half-life extending moiety to improve t½. Intl. Patent Application Publication No. WO 2017/201340 describes analogs that are fusions of the A chain and B chain having a variable light chain fragment to improve t½. Intl. Patent Application Publication No. WO 2015/067791 describes analogs that are carrier-linked prodrugs, especially PEG-based carriers, to improve t½ (see also, WO 2012/024452 for additional PEG-linked analogs). Intl. Patent Application Publication No. WO 2014/102179 describes analogs that are fusions of the A chain and B chain having a Fc moiety of IgG2 or IgG4 to improve t½. Intl. Patent Application Publication No. WO 2013/004607 describes analogs that are fusions of the A chain and B chain having a linker of at least five amino acids but less than fifteen amino acids to improve t½ or that are fusions of the A chain and B chain having a Fc domain of antibodies to improve t½.

[0005] In view of the increases in understanding the various physiological roles of RLNs, there remains a need for long-acting RLN analogs having an improved t½.

[0006] To address this need, the disclosure first describes single-chain RLN analogs having principal activity at the RXFP1 receptor (i.e., act as RXFP1 receptor agonists). Such RXFP1 receptor agonists include a basic structure from an amino-terminus (N-terminus) to a carboxy-terminus (C-terminus) of:

VHH-L1-A-L2-B,

VHH-L1-B-L2-A,

A-L2-B-L1-VHH, or

B-L2-A-L1-VHH,

where VHH is a moiety that can act as a pharmacokinetic enhancer, A is a RLN A chain, B is a RLN B chain, L1 is a first linker, and L2 is a second linker.

[0007] In some instances, the VHH moiety can have an amino acid sequence of SEQ ID NO:10, 11, 12 or 13, especially SEQ ID NO:10 or 12. In other instances, the VHH moiety can have one or more additions, deletions, insertions or substitutions such that the VHH moiety has an amino acid sequence having at least about 90% to about 99% sequence similarity to any one of SEQ ID NOS:10, 11, 12 or 13 (see, e.g., SEQ ID NOS:45-66).

[0008] In some instances, the A chain can have an amino acid sequence of SEQ ID NO:2, 5 or 8, especially SEQ ID NO:5. In other instances, the A chain can have one or more additions, deletions, insertions or substitutions such that the A chain has an amino acid sequence having at least about 90% to about 99% sequence similarity to any one of SEQ ID NOS:2, 5 or 8. For example, the A chain can be des1-4 of SEQ ID NO:5.

[0009] In some instances, the B chain can have an amino acid sequence of SEQ ID NO:3, 6 or 9, especially SEQ ID NO:6. In other instances, the B chain can have one or more additions, deletions, insertions or substitutions such that the B chain has an amino acid sequence having at least about 90% to about 99% sequence similarity to any one of SEQ ID NOS:3, 6 or 9. For example, the B chain can be des1 of SEQ ID NO:6.

[0010] In some instances, L1 can have an amino acid sequence of (GGGGQ)n (SEQ ID NO:14), (GGGQ)n (SEQ ID NO:15), (GGGGS)n (SEQ ID NO:16), (PGPQ)n (SEQ ID NO:17) or (PGPA)n (SEQ ID NO:18), where n can be from 1 to 10, especially from about 5 to about 8. In other instances, L1 can have an amino acid sequence of SEQ ID NO:19, 20 or 21. In still other instances, L1 can have one or more additions, deletions, insertions or substitutions such that L1 has an amino acid sequence having at least about 90% to about 99% sequence similarity to any one of SEQ ID NOS:14 to 21.

[0011] In some instances, L2 can have an amino acid sequence of SEQ ID NO:22, 23 or 67. In other instances, L2 can have one or more additions, deletions, insertions or substitutions.

[0012] In certain instances, the RLN analogs can have an amino acid sequence that includes a VHH of SEQ ID NO:10, 11, 12 or 13; an A chain of SEQ ID NO:2, 5 or 8; a B chain of SEQ ID NO:3, 6 or 9; a L1 of SEQ ID NO:19, 20 or 21; and a L2 of SEQ ID NO:22, 23 or 67. Alternatively, the RLN analogs can have an amino acid sequence having at least about 90% to about 99% sequence similarity to an amino acid sequence that includes an amino acid sequence that includes a VHH of SEQ ID NO:10, 11, 12 or 13; an A chain of SEQ ID NO:2, 5 or 8; a B chain of SEQ ID NO:3, 6 or 9; a L1 of SEQ ID NO:19, 20 or 21; and a L2 of SEQ ID NO:22, 23 or 67.

[0013] In particular instances, the RLN analogs can have an amino acid sequence of SEQ ID NO:24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38 or 39, especially SEQ ID NO:26, 27, 30, 31, 34 or 35. Alternatively, the RLN analogs can have an amino acid sequence having at least about 90% to about 99% sequence similarity to an amino acid sequence of SEQ ID NO:24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38 or 39, especially SEQ ID NO:26, 27, 30, 31, 34 or 35.

[0014] In some instances, the RLN analogs have a binding affinity at a RXFP1 receptor that is comparable to the binding affinity of native, human RLN2 (SEQ ID NOS:5 and 6). In other instances, the RLN analogs have a binding affinity at a RXFP1 receptor that is greater than that of native, human RLN2 (SEQ ID NOS:5 and 6). In still other instances, the RLN analogs have a binding affinity at a RXFP1 receptor that is less than that of native, human RLN2 (SEQ ID NOS:5 and 6).

[0015] In some instances, the RLN analogs have a t½ that is longer than that of native, human RLN2 (SEQ ID NOS:5 and 6), including up to about 20 days to about 30 days longer when administered to a human.

[0016] The compositions above alternatively can be nucleic acid sequences encoding the amino acid sequences described herein, as well as vectors and host cells including the same for expressing the RLN analogs herein.

[0017] Second, pharmaceutical compositions are described that include at least one RLN analog herein or a pharmaceutically acceptable salt thereof (e.g., trifluroacetate salts, acetate salts or hydrochloride salts) and a pharmaceutically acceptable carrier. In some instances, the pharmaceutically acceptable carrier is a buffer such as, for example, physiological saline, phosphate-buffered saline, citrate-buffered saline or histidine-buffered saline. In certain instances, the buffer is histidine, a histidine buffer or a histidine-buffered saline. In other instances, the pharmaceutical compositions further can include carriers, diluents and/or excipients.

[0018] Moreover, the pharmaceutical compositions can include at least one additional therapeutic agent such as, for example, an agent used as a standard of care in a cardiovascular, pulmonary and/or renal condition, disease or disorder. In some instances, the at least one additional therapeutic agent can be an anticoagulant, an angiotensin-converting enzyme (ACE) inhibitor, an angiotensin II receptor blocker (ARB), an ARB neprilysin inhibitor (ARNI), a b-blocker, a diuretic, digitalis, digoxin, hydralazine/isorbide dinitrate, a mineralocorticoid receptor antagonist (MRA; or aldosterone antagonist), a sodium-glucose cotransporter-2 (SGLT2) inhibitor, a statin and/or an anti-glycemic agent.

[0019] Third, methods are described for using the RLN analogs herein, especially for using the RLN analogs to treat cardiovascular, pulmonary and/or renal conditions, diseases or disorders. The methods include at least a step of administering to an individual in need

thereof an effective amount of at least one RLN analog herein or a pharmaceutically acceptable salt thereof.

[0020] In some instances, the RLN analog can be administered via any standard route of administration such as, for example, intramuscularly, intravenously, parenterally, subcutaneously or transdermally. In certain instances, the RLN analog is administered subcutaneously (SQ), intramuscularly (IM) or intravenously (IV). In particular instances, the RLN analog can be administered SQ or IV to the individual.

[0021] Likewise, and in some instances, the RLN analog can be administered daily, every other day, three times a week, two times a week, one time a week (i.e., weekly), biweekly (i.e., every other week), one time a month (i.e., monthly), bimonthly (i.e., every other month), or even every three months. In certain instances, the RLN analog can be administered SQ every other day, SQ three times a week, SQ two times a week, SQ one time a week, SQ every other week, or SQ once a month. In particular instances, the RLN analog is administered SQ one time a week (QW).

[0022] Alternatively, the RLN analog can be IV administered to the individual. As above, the RLN analog can be administered daily, every other day, three times a week, two times a week, one time a week (i.e., weekly), biweekly (i.e., every other week), or monthly. In certain instances, the RLN analog can be administered IV every other day, IV three times a week, IV two times a week, IV one time a week, IV every other week, or IV once a month. In particular instances, the RLN analog is administered IV one time a week.

[0023] The methods also can include a step of administering the RLN analog in combination with an effective amount of at least one additional therapeutic agent. Briefly, the standard of care for many of the conditions/diseases/disorders herein includes an anticoagulant, an ACE inhibitor, an ARB, an ARNI, a b-blocker, a diuretic, digitalis, digoxin, hydralazine/isorbide dinitrate, a MRA or other aldosterone antagonist, a SGLT2 inhibitor, a statin and/or an anti-glycemic agent, as well as other therapeutic agents to control comorbidities, including, but not limited to, high cholesterol, high blood pressure, atrial fibrillation and diabetes. In some instances, the additional therapeutic agent can be administered simultaneously, separately or sequentially with the RLN analog.

[0024] For example, the additional therapeutic agent can be administered with a frequency the same as the RLN analog (i.e., every other day, twice a week, weekly or even monthly). In other instances, the additional therapeutic agent can be administered with a frequency distinct from the RLN analog. In other instances, the additional therapeutic agent can be administered SQ or IV. In still other instances, the RLN analog is administered SQ, and the additional therapeutic agent can be administered orally or IV. Alternatively, the RLN analog is administered IV, and the additional therapeutic agent is administered SQ.

[0025] In some instances, the individual in need is a diabetic, hypertensive with kidney function impairment and/or obese.

[0026] The methods also may include steps such as measuring or obtaining blood pressure and comparing such obtained values to one or more baseline values or previously obtained values to assess the effectiveness of treatment/therapy.

[0027] The methods also may be combined with diet and exercise and/or may be combined with additional therapeutic agents other than those discussed above.

[0028] Fourth, uses are described that include at least one of the RLN analogs herein. For example, the RLN analogs herein can be provided for use in therapy, especially in treating cardiovascular, pulmonary and/or renal conditions, diseases or disorders. The RLN analogs optionally can be administered simultaneously, separately or sequentially (i.e., in combination) with at least one additional therapeutic agent. Likewise, use of the RLN analogs herein is provided in manufacturing a medicament for treating cardiovascular, pulmonary and/or renal conditions, diseases or disorders, where the medicament optionally may further include one or more additional therapeutic agents as noted above.

[0029] Fifth, a compound is provided that includes an amino acid sequence of:

EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:10). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:10.

[0030] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSSPP (SEQ ID NO:11). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:11.

[0031] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKGREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:12). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:12.

[0032] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKGREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSSPP (SEQ ID NO:13). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:13.

[0033] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRTVSSTAVAWFRQAPGKEREFVAGIGGS VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAVRPGRPLITSRD ANLYDYWGQGTLVTVSS (SEQ ID NO:45). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:45.

[0034] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDSTAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSRV ANLYPYWGQGTLVTVSS (SEQ ID NO:46). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:46.

[0035] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASYRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:47). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:47.

[0036] Alternatively, a compound is provided that includes an amino acid sequence of:

EVQLLESGGGLVQPGGSLRLSCAASGAYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:48). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:48.

[0037] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDETYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:49). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:49.

[0038] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDQTYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSK VADLYPYWGQGTLVTVSS (SEQ ID NO:50). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:50.

[0039] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITAYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:51). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:51.

[0040] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITEYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:52). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:52.

[0041] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITQYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV

ADLYPYWGQGTLVTVSS (SEQ ID NO:53). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:53.

[0042] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITSYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:54). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:54.

[0043] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITTYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:55). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:55.

[0044] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGKPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:56). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:56.

[0045] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGQPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:57). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:57.

[0046] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGSPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:58). In some instances, the compound can have

an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:58.

[0047] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRELITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:59). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:59.

[0048] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRQLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:60). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:60.

[0049] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRSLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:61). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:61.

[0050] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPEITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:62). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:62.

[0051] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPGITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:63). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:63.

[0052] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPQITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:64). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:64.

[0053] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPTITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:65). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:65.

[0054] Alternatively, a compound is provided that includes an amino acid sequence of: EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITEKV ADLYPYWGQGTLVTVSS (SEQ ID NO:66). In some instances, the compound can have an amino acid sequence having at least about 90% to about 99% sequence similarity to SEQ ID NO:66.

[0055] An advantage of the RLN analogs herein is that they can be chemically or recombinantly synthesized as a single-chain polypeptide (i.e., monomeric) and thus do not require endoproteolytic processing for biological activity. It is contemplated, however, that in some instances, the VHH moiety can be conjugated not only to single-chain RLNs but also to two-chain RLNs (e.g., native). On the VHH moiety, one could conjugate not only to the N- and C-terminus but also to any surface-exposed amino acid of the VHH (with the proviso that such conjugation does not entirely abrogate albumin binding).

[0056] An advantage of the RLN analogs herein is that the VHH moieties can be used not only with native A chain and B chain sequences but also with modified sequences thereof. Moreover, the VHH moieties may be further modified to have enhanced or additional functionality via other peptide/protein fusions or small molecules being attached to the VHH moieties.

[0057] An advantage of the RLN analogs herein is that the VHH moieties provide an extended duration of action in mammals such as humans and can have a t½ of about 20

days to about 30 days, thereby allowing for at least weekly or biweekly administration when compared to native, human RLN, especially native, human RLN2 (SEQ ID NOS:5 and 6), which can improve compliance.

[0058] An advantage of the RLN analogs herein is that they have similar or better selectivity, affinity and/or potency for RXFP1 than RXFP2 receptors when compared to native, human RLN2 (SEQ ID NOS:5 and 6). Alternatively stated, the RLN analogs herein result in sufficient activity at RXFP1 receptor and reduced or insufficient activity at one or more of the RXFP2, RXFP3 and RXFP4 receptors.

[0059] An advantage of the RLN analogs herein is that they have tunable pharmacokinetics achieved by changing albumin affinity of the VHH moieties.

[0060] An advantage of the RLN analogs herein is that they have improved stability in a preserved formulation when compared to native, human RLN2 (SEQ ID NOS:5 and 6) or RLN analogs having an Fc fusion.

[0061] Moreover, an advantage of the VHH moieties is that they have equal binding not only to human serum albumin but also to dog, monkey, mouse, pig and rat serum albumin, which allows for pharmacodynamic, pharmacokinetic and toxicology studies to more readily translate from these species to humans.

[0062] An advantage of the VHH moieties is that they not only can be used to improve the t½ of the RLN analogs herein when compared to native, human RLN2 (SEQ ID NOS:5 and 6) but also can be used to improve the t½ of other biologically active peptides and proteins such as, for example, insulin, growth differentiation factor 15 (GDF-15) or glucose-dependent insulinotropic peptide 1 (GLP-1).

[0063] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art to which the disclosure pertains. Although any methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the RLN analogs, pharmaceutical compositions and methods, the preferred methods and materials are described herein.

[0064] Moreover, reference to an element by the indefinite article“a” or“an” does not exclude the possibility that more than one element is present, unless the context clearly requires that there be one and only one element. The indefinite article“a” or“an” thus usually means“at least one.”

[0065] Definitions

[0066] As used herein,“about” means within a statistically meaningful range of a value or values such as, for example, a stated concentration, length, molecular weight, pH, sequence similarity, time frame, temperature, volume, etc. Such a value or range can be within an order of magnitude typically within 20%, more typically within 10%, and even more typically within 5% of a given value or range. The allowable variation encompassed by“about” will depend upon the particular system under study, and can be readily appreciated by one of skill in the art.

[0067] As used herein, and in reference to one or more of the RXFP receptors,“activity,” “activate,”“activating” and the like means a capacity of a compound, such as a RLN analog herein, to bind to and induce a response at its receptor(s), as measured using assays known in the art, such as the in vitro assays described below.

[0068] As used herein,“amino acid” means a molecule that, from a chemical standpoint, is characterized by a presence of one or more amine groups and one or more carboxylic acid groups, and may contain other functional groups. As is known in the art, there is a set of twenty amino acids that are designated as standard amino acids and that can be used as building blocks for most of the peptides/proteins produced by any living being. The amino acid sequences in the disclosure contain the standard single letter or three letter codes for the twenty standard amino acids.

[0069] As used herein,“analog” means a compound, such as a synthetic peptide or polypeptide, that activates a target receptor and that elicits at least one in vivo or in vitro effect elicited by a native agonist for that receptor.

[0070] As used herein,“conservative substitution” means a variant of a reference peptide or polypeptide that is identical to the reference molecule, except for having one or more conservative amino acid substitutions in its amino acid sequence. In general, a conservatively modified variant includes an amino acid sequence that is at least about 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a reference amino acid sequence. More specifically, a conservative substitution refers to substitution of an amino acid with an amino acid having similar characteristics (e.g., charge, side-chain size, hydrophobicity/hydrophilicity, backbone conformation and rigidity, etc.) and having minimal impact on the biological activity of the resulting substituted peptide or polypeptide. Conservative substitutions of functionally similar amino acids are well known in the art and thus need not be exhaustively described herein.

[0071] As used herein,“effective amount” means an amount or dose of one or more RLN analogs herein, or a pharmaceutically acceptable salt thereof that, upon single or multiple dose administration to an individual in need thereof, provides a desired effect in such an individual under diagnosis or treatment (i.e., may produce a clinically measurable difference in a condition of the individual such as, for example, increased angiogenesis, increased vascular compliance, increased cardiac blood flow, increased hepatic blood flow, increased pulmonary blood flow, increased renal blood flow, increased glomerular filtration rate, decreased blood pressure, decreased (or prevented) inflammation and/or reduced (or prevented) fibrosis in the heart, kidney, liver or lung). An effective amount can be readily determined by one of skill in the art by using known techniques and by observing results obtained under analogous circumstances. In determining the effective amount for an individual, a number of factors are considered, including, but not limited to, the species of mammal, its size, age and general health, the specific disease or disorder involved, the degree of or involvement or the severity of the disease or disorder, the response of the individual, the particular RLN analog administered, the mode of administration, the bioavailability characteristics of the preparation administered, the dose regimen selected, the use of concomitant medication, and other relevant circumstances.

[0072] As used herein,“extended duration of action” means that binding affinity and activity for a RLN analog herein continues for a period of time greater than a native RLN, especially native, human RLN2 (SEQ ID NOS:5 and 6), allowing for dosing at least as infrequently as once daily or even thrice-weekly, twice-weekly or once-weekly. The time action profile of the RLN analog may be measured using known pharmacokinetic test methods such as those utilized in the Examples below.

[0073] As used herein,“half-life” or“t½” means a time it takes for one-half of a quantity of a compound, such as native RLN or a RLN analog herein, to be removed from a fluid or other physiological space such as serum or plasma of an individual by biological processes. Alternatively, t½ also can mean a time it takes for a quantity of such a compound to lose one-half of its pharmacological, physiological or radiological activity.

[0074] As used herein,“half-maximal effective concentration” or“EC50” means a concentration of compound that results in 50% activation/stimulation of an assay endpoint, such as a dose-response curve (e.g., cAMP, PI3K-Akt, NFkb, VEGF and/or nitric oxide (NO) signaling pathways).

[0075] As used herein,“in combination with” means administering at least one of the RLN analogs herein either simultaneously, sequentially or in a single combined formulation with one or more additional therapeutic agents.

[0076] As used herein,“individual in need thereof” means a mammal, such as a human, with a condition, disease, disorder or symptom requiring treatment or therapy, including for example, those listed herein. In particular, the individual to be treated is a human.

[0077] As used herein,“long-acting” means that binding affinity and activity of a RLN analog herein continues for a period of time greater than native, human RLN2 (SEQ ID NOS:5 and 6), allowing for dosing at least as infrequently as once daily or even thrice-weekly, twice-weekly, once-weekly or monthly. The time action profile of the RLN analogs may be measured using known pharmacokinetic test methods such as those described in the Examples below.

[0078] As used herein,“non-standard amino acid” means an amino acid that may occur naturally in cells but does not participate in peptide synthesis. Non-standard amino acids can be constituents of a peptide and often are generated by modifying standard amino acids in the peptide (i.e., via post-translational modification). Non-standard amino acids can include D-amino acids, which have an opposite absolute chirality of the standard amino acids above.

[0079] As used herein,“pharmaceutically acceptable buffer” means any of the standard pharmaceutical buffers known to one of skill in the art.

[0080] As used herein,“RLN” means a relaxin obtained or derived from any species, such as a mammalian species, especially a human, where the native form is a heterodimeric peptide having two peptide chains (e.g., an A chain and a B chain) connected via two disulfide bonds, and with the A chain further having a single intramolecular disulfide bond. RLN includes both native RLN (i.e., full-length) and variations thereof (i.e., additions, deletions, insertions and/or substitutions of native RLN). In humans, there are three native RLN isoforms– RLN1, RLN2 and RLN3. RLN processing begins with preprorelaxin, which is processed to prorelaxin (includes A chain, B chain and C peptide; native RLN has a structure of B-C-A), where the sequence of native, human proRLN1 is set forth in SEQ ID NO:1 (see also, UniProt/SwissProt Database Accession No. P04808), the sequence of

native, human proRLN2 is set forth in SEQ ID NO:4 (see also, UniProt/SwissProt Database Accession No. P04090), and the sequence of native, human proRLN3 is set forth in SEQ ID NO:7 (see also, UniProt/SwissProt Database Accession No. Q8WXF3). Prorelaxin undergoes further processing in which the C peptide is cleaved to arrive at RLN. The sequences for the A chain of native, human RLN1, RLN2 and RLN3 are set forth in SEQ ID NOS:2, 5 and 8, respectively. Likewise, the sequences for the B chain of native, human RLN1, RLN2 and RLN3 are set forth in SEQ ID NOS:3, 6 and 9, respectively.

[0081] In humans, there are four RLN receptors– RXFP1 (SEQ ID NO:40; see also, UniProt/SwissProt Database Accession No. Q9HBX9), RXFP2 (SEQ ID NO:41; see also, UniProt/SwissProt Database Accession No. Q8WXD0), RXFP3 (SEQ ID NO:42; see also, UniProt/SwissProt Database Accession No. Q9NSD7) and RXFP4 (SEQ ID NO:43; see also, UniProt/SwissProt Database Accession No. Q8TDU9)– that act as GPCRs (see, Halls et al. (2007) Br. J. Pharmacol.150:677-691). Of interest herein are the RXFP1 and RXFP2 receptors, both of which can bind RLN1 and RLN2. The RXFP1 receptor has been found in the brain, blood cells, bone, heart, kidney, lung, liver and vasculature, whereas the RXFP2 receptor is much more restricted and has been found in the bone and gubernaculum. Stimulation of the RXFP1 and RXFP2 receptors activates signal transduction networks involving adenylate cyclase, protein kinase A, protein kinase C, phosphatidylinositol 3-kinase and/or extracellular signal-regulated kinases (Erk1/2).

[0082] As used herein,“RLN analog” and the like means a compound, such as a peptide or polypeptide, that elicits one or more effects of native RLN at one or more RXFP receptors but varies in some manner with respect to the amino acid sequence when compared native RLN. RLN analog also can include variants of these compounds, which are functionally equivalent to RLN but have sequences that are fragments or are the complete sequence but having additions, deletions, insertions and/or substitutions. All references to amino acid positions in unmodified or modified RLNs described herein are based on the corresponding position in the A chain of SEQ ID NO:5 or the B chain of SEQ ID NO:6 of native, human RLN2, unless otherwise specified. In some instances, the RLN analogs herein can bind to a RXFP with higher or lower affinity but demonstrate a longer t½ in vivo or in vitro when compared to native RLN, especially a native, human RLN2 (SEQ ID NOS:5 and 6). In this manner, the RLN analogs herein are synthetic compounds that act as RXFP receptor agonists.

[0083] As used herein,“sequence similarity” means a quantitative property of two or more nucleic acid sequences or amino acid sequences of biological compounds such as, for example, a correspondence over an entire length or a comparison window of the two or more sequences. Sequence similarity can be measured by (1) percent identity or (2) percent similarity. Percent identity measures a percentage of residues identical between two biological compounds divided by the length of the shortest sequence; whereas percent similarity measures identities and, in addition, includes sequence gaps and residue similarity in the evaluation. Methods of and algorithms for determining sequence similarity are well known in the art and thus need not be exhaustively described herein. A specified percentage of identical nucleotide or amino acid positions is at least about 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher.

[0084] As used herein,“single-chain relaxin,”“scRLN” and the like means a RLN polypeptide where the A and B chains are connected to one another by a linker (i.e., L2) as in A-L2-B or B-L2-A. Moreover, scRLN can include at least one of the native interchain and/or intrachain disulfide bonds to maintain correct structural folding.

[0085] As used herein,“two-chain relaxin,”“tcRLN” and the like means a RLN polypeptide where the A and B chains are connected to one another by one or more interchain and/or intrachain disulfide bonds, but not by any linkers, to maintain correct structural folding, such as a native RLN.

[0086] As used herein,“treating” or“to treat” means managing and caring for an individual having a condition, disease, disorder or symptom for which RLN analog administration is indicated for the purpose of attenuating, restraining, reversing, slowing or stopping progression or severity of the condition, disease, disorder and/or symptom. Treating includes administering a RLN analog herein or composition containing a RLN analog herein to the individual to prevent the onset of symptoms or complications, alleviating the symptoms or complications, or eliminating the condition, disease, disorder or symptom. Treating includes administering a RLN analog or composition containing a RLN analog herein to the individual to result in such as, for example, increased angiogenesis, increased vascular compliance, increased cardiac blood flow, increased hepatic blood flow, increased pulmonary blood flow, increased renal blood flow, increased glomerular filtration rate, decreased blood pressure, decreased (or prevented) inflammation and/or reduced (or prevented) fibrosis in the heart, kidney, liver or lung). The individual to be treated is a mammal, especially a human.

[0087] As used herein,“individual,”“patient” and“subject” are used interchangeably and mean a mammal, especially a human. In certain instances, the individual is further characterized with a condition, disease, disorder and/or symptom that would benefit from administering a RLN analog herein.

[0088] As used herein,“VHH” or“VHH moiety” means a form of single-domain antibody, especially an antibody fragment of a single, monomeric variable region of a heavy chain only antibody (HcAb), which has a very small size of about 15 kDa. It has been found herein that VHH moieties can be used as a pharmacokinetic enhancer to extend the duration of action of and/or to improve the t½ of the RLN analogs herein. The VHH moieties herein bind serum albumin; however, the VHH moieties can be used to bind IgG (including Fc domain), neonatal Fc receptor (FcRn) or other long-lasting serum proteins. Although the VHH moieties herein are used to improve the t½ of RLN, they likewise can be used to improve the t½ of other biologically active peptides/proteins such as, for example, insulin, GDF-15 or GLP-1.

[0089] Certain abbreviations are defined as follows: “ACR” refers to urine albumin/urine creatinine ratio;“amu” refers to atomic mass unit;“AUC” refers to area under the curve;“Boc” refers to tert-butoxycarbonyl;“cAMP” refers to cyclic adenosine monophosphate;“CMV” refers to cytomegalovirus;“CV” refers to column volume; “DNA” refers to deoxyribonucleic acid;“DMF” refers to dimethylformamide;“DMSO” refers to dimethyl sulfoxide; “EDC” refers to 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride; “EDTA” refers to ethylenediaminetetraacetic acid; “EIA/RIA” refers to enzyme immunoassay/radioimmunoassay; “ETA” refers to ethanolamine;“GS” refers to glutamine synthetase;“HIC” refers to hydrophobic interaction chromatography;“hr” refers to hour or hours;“HTRF” refers to homogenous time-resolved fluorescent;“IV” refers to intravenous;“IP” refers to intraperitoneal;“kDa” refers to kilodaltons;“LC/MS” refers to liquid chromatography-mass spectrometry;“min” refers to minute or minutes;“MS” refers to mass spectrometry;“MSX” refers to methionine sulfoximine;“NaOAc” refers to sodium acetate;“NHS” refers to N-hydroxysuccinimide; “OtBu” refers to O-tert-butyl; “Pbf” refers to NG-2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl;“PEI” refers to polyethylenimine;“RP-HPLC”

refers to reversed-phase high performance liquid chromatography;“RU” means resonance units;“sec” refers to second or seconds;“SPR” refers to surface plasmon resonance;“SQ” refers to subcutaneous;“SEC” refers to size-exclusion chromatography;“SEM” refers to standard error of the mean;“TFA” refers to trifluoroacetic acid; and“Trt” refers to trityl.

[0090] RLN Analogs

[0091] The RLN analogs herein have structural similarities to, but many structural differences, from native, human RLN. For example, when compared to native, human RLN2 (SEQ ID NOS:5 and 6), the RLN analogs lack one or more of the amino acids present in native, human RLN2, include a peptide linker between the A chain and the B chain, and include an albumin-binding VHH moiety. The RLN analogs result in sufficient activity at the RXFP1 receptor and reduced or insufficient activity at one or more of the RXFP2, RXFP3 and RXFP4 receptors. Likewise, the RLN analogs have beneficial attributes relevant to their developability as therapeutic treatments, including improved solubility in aqueous solutions, improved chemical and physical formulation stability, extended pharmacokinetic profile (which can be tuned based upon VHH affinity to serum albumin), and/or minimized potential for immunogenicity.

[0092] Briefly, the RLN analogs herein include an amino acid sequence from the N-terminus to the C-terminus having one of the following structures:

VHH-L1-A-L2-B,

VHH-L1-B-L2-A,

A-L2-B-L1-VHH, or

B-L2-A-L1-VHH,

where VHH is a moiety acting as a pharmacokinetic enhancer, A is a RLN A chain, B is a RLN B chain, L1 is a first peptide linker and L2 is a second peptide linker, where L1 and L2 are distinct from one another (i.e., each have an amino acid sequence that is not the same).

[0093] With regard to the A chain, it can be a native RLN A chain, such as a native, human RLN1 A chain (SEQ ID NO:2); native, human RLN2 A chain (SEQ ID NO:5); or native, human RLN3 A chain (SEQ ID NO:8). Alternatively, the A chain can be a variant thereof. For example, one A chain variant can have an amino acid sequence that lacks residues 1 to 4 of SEQ ID NO:5 (i.e., des1-4 human RLN2 A chain or desA1-4).

[0094] Likewise, and with regard to the B chain, it can be a native RLN B chain, such as a native, human RLN1 B chain (SEQ ID NO:3); native, human RLN2 B chain (SEQ ID NO:6); or native, human RLN3 B chain (SEQ ID NO:9). Alternatively, the B chain can be a variant thereof. For example, one B chain variant can have an amino acid sequence that lacks residue 1 of SEQ ID NO:6 (i.e., des1 human RLN2 B chain or desB1).

[0095] In some instances, the A chain can be a native, human RLN1 A chain (SEQ ID NO:2) and the B chain can be a native, human RLN1 B chain (SEQ ID NO:3); the A chain can be a native, human RLN2 A chain (SEQ ID NO:5) and the B chain can be a native, human RLN2 B chain (SEQ ID NO:6); the A chain can be a native, human RLN3 A chain (SEQ ID NO:8) and the B chain can be a native, human RLN3 B chain (SEQ ID NO:9); the A chain can be a native, human RLN1 A chain (SEQ ID NO:2) and the B chain can be a native, human RLN2 B chain (SEQ ID NO:6); the A chain can be a native, human RLN1 A chain (SEQ ID NO:2) and the B chain can be a native, human RLN3 B chain (SEQ ID NO:9); the A chain can be a native, human RLN2 A chain (SEQ ID NO:5) and the B chain can be a native, human RLN1 B chain (SEQ ID NO:3); the A chain can be a native, human RLN2 A chain (SEQ ID NO:5) and the B chain can be a native, human RLN3 B chain (SEQ ID NO:9); the A chain can be a native, human RLN3 A chain (SEQ ID NO:8) and the B chain can be a native, human RLN1 B chain (SEQ ID NO:3); or the A chain can be a native, human RLN3 A chain (SEQ ID NO:8) and the B chain can be a native, human RLN2 B chain (SEQ ID NO:6).

[0096] In some instances, the A chain may be a RLN2 A chain variant that lacks residues 1 to 4 (desA1-4) and the B chain may be any native B chain. In other instances, the A chain may be any native A chain and the B chain may be a RLN2 B chain variant that lacks residue 1 (desB1). In yet other instances, the A chain may be a RLN2 A chain variant that lacks residues 1 to 4 (desA1-4) and the B chain may be a RLN2 B chain variant that lacks residue 1 (desB1). In certain instances, the A chain is the desA1-4 variant. In certain instances, the B chain is the desB1 variant.

[0097] Other A and B chains that can be used in the RLN analogs herein are described in, for example, Intl. Patent Application Publication Nos. WO 2018/148419, WO 2018/138170, WO 2017/201340, WO 2016/149501, WO 2015/157829, WO 2015/067791, WO 2015/067113, WO 2014/102179, WO 2013/177529, WO 2013/007563, WO 2013/004607, WO 2012/031326 and WO 2012/024452; and US Patent Application

Publication No. US 2011/0243942. See also, Chan et al. (2012) J. Biol. Chem.287:41152-41164; Claasz et al. (2002) Eur. J. Biochem. 269:6287-6293; Hossain et al. (2015) Org. Biomol. Chem.13:10895-10890; Hossain et al. (2016) Chem. Sci.7:3805-3819; Park et al. (2008) J. Biol. Chem.283:32099-32109 and Wilkinson et al. (2005) BMC Evol. Biol.5:14.

[0098] With regard to L1, it can be a peptide of about 1 amino acid to about 50 amino acids. Alternatively, L1 can be from about 1, about 5, about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45 or about 50 amino acids. Alternatively still, L1 can be from about 5 amino acids to about 10 amino acids, from about 10 amino acids to about 15 amino acids, from about 15 amino acids to about 20 amino acids, from about 20 amino acids to about 25 amino acids, from about 25 amino acids to about 30 amino acids, from about 30 amino acids to about 35 amino acids, from about 35 amino acids to about 40 amino acids, from about 40 amino acids to about 45 amino acids, or from about 45 amino acids to about 50 amino acids. In some instances, L1 may be omitted such that the A chain or B chain is directly conjugated to the VHH moiety. In some instances, L1 can include a repeating sequence of (GGGGQ)n (SEQ ID NO:14), where n can be from about 1 to about 10, especially 5 (i.e., (GGGGQ)5; SEQ ID NO:19). In other instances, L1 can include a repeating sequence of (PGPQ)n (SEQ ID NO:17), where n can be from about 1 to about 10, especially 8 (i.e., (PGPQ)8; SEQ ID NO:20). In still other instances, L1 can include a repeating sequence of (PGPA)n (SEQ ID NO:18), where n can be from about 1 to about 10, especially 8 (i.e., (PGPA)8; SEQ ID NO:21).

[0099] Other linkers that can be used in the RLN analogs as L1 include, but are not limited to, (GGGQ)n (SEQ ID NO:15) or (GGGGS)n (SEQ ID NO:16).

[0100] With regard to L2, it can be a peptide of about 1 amino acid to about 15 amino acids. Alternatively, L2 can be about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, or about 15 amino acids. Alternatively still, L2 can be about 1 amino acid to about 5 amino acids, about 5 amino acids to about 10 amino acids, about 10 amino acids to about 15 amino acids, especially 10 amino acids to 15 amino acids. In some instances, L2 can include a mix of Ala/A, Gln/Q, Gly/G, Pro/P and Ser/S residues. In other instances, L2 can be SEQ ID NO:22, 23 or 67.

CLAIMS

The invention claimed is:

1. A compound comprising a structure of:

VHH-L1-A-L2-B,

VHH-L1-B-L2-A,

A-L2-B-L1-VHH, or

B-L2-A-L1-VHH,

wherein VHH comprises an amino acid sequence selected from the group consisting of SEQ ID NOS:10, 11, 12 and 13 or a sequence having at least 90% sequence similarity thereto,

wherein A is a relaxin A chain comprising an amino acid sequence selected from the group consisting of SEQ ID NOS:2, 5 and 8 or a sequence having at least 90% sequence similarity thereto,

wherein B is a relaxin B chain comprising an amino acid sequence selected from the group consisting of SEQ ID NOS:3, 6 and 9 or a sequence having at least 90% sequence similarity thereto,

wherein L1 is a first linker comprising an amino acid sequence selected from the group consisting of (GGGGQ)n (SEQ ID NO:14), (PGPQ)n (SEQ ID NO:17) and (PGPA)n (SEQ ID NO:18), and wherein n can be from 1 to 10, and

wherein L2 is a second linker comprising an amino acid sequence selected from the group consisting of SEQ ID NOS:22, 23 and 67; or

a pharmaceutically acceptable salt thereof.

2. The compound of Claim 1, wherein A is SEQ ID NO:2.

3. The compound of Claims 1 or 2, wherein B is SEQ ID NO:3.

4. The compound of Claim 1, wherein A is SEQ ID NO:5.

5. The compound of Claims 1 or 2, wherein B is SEQ ID NO:6.

6. The compound of Claim 1, wherein A is SEQ ID NO:5 and lacks the first four amino acids (desA1-4).

7. The compound of Claim 1, wherein B is SEQ ID NO:6 and lacks the first amino acid (desB1).

8. The compound of Claim 1, wherein A is SEQ ID NO:5 and lacks the first four amino acids (desA1-4), and wherein B is SEQ ID NO:6 and lacks the first amino acid (desB1).

9. The compound of Claim 1, wherein A is SEQ ID NO:8.

10. The compound of Claims 1 or 2, wherein B is SEQ ID NO:9.

11. The compound of any one of Claims 1 to 10, wherein L1 is SEQ ID NO:19.

12. The compound of any one of Claims 1 to 10, wherein L1 is SEQ ID NO:20.

13. The compound of any one of Claims 1 to 10, wherein L1 is SEQ ID NO:21.

14. A compound comprising an amino acid sequence selected from the group consisting of SEQ ID NOS:24 to 39 or a sequence having at least 90% sequence similarity thereto or a pharmaceutically acceptable salt thereof.

15. A compound consisting essentially of an amino acid sequence selected from the group consisting of SEQ ID NOS:24 to 39 or a sequence having at least 90% sequence similarity thereto or a pharmaceutically acceptable salt thereof.

16. A compound consisting of an amino acid sequence selected from the group consisting of SEQ ID NOS:24 to 39 or a sequence having at least 90% sequence similarity thereto or a pharmaceutically acceptable salt thereof.

17. A pharmaceutical composition comprising:

a compound of any one of Claims 1 to 16 or a pharmaceutically acceptable salt thereof; and

a pharmaceutically acceptable buffer.

18. A method of treating cardiac, pulmonary and/or renal conditions, diseases and/or disorders in an individual, the method comprising the step of:

administering to the individual an effective amount of a compound of any one of Claims 1 to 16 or a pharmaceutical composition of Claim 17.

19. A compound of any one of Claims 1 to 16 for use in a therapy.

20. A compound of any one of Claims 1 to 16 for use in treating cardiac, pulmonary and/or renal conditions, diseases and/or disorders.

21. Use of a compound of any one of Claims 1 to 16 for manufacturing a medicament for treating cardiac, pulmonary and/or renal conditions, diseases and/or disorders.

22. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:10) or a sequence having at least 90% sequence similarity thereto.

23. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSSPP (SEQ ID NO:11) or a sequence having at least 90% sequence similarity thereto.

24. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKGREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:12) or a sequence having at least 90% sequence similarity thereto.

25. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKGREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSSPP (SEQ ID NO:13) or a sequence having at least 90% sequence similarity thereto.

26. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRTVSSTAVAWFRQAPGKEREFVAGIGGS VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAVRPGRPLITSRD ANLYDYWGQGTLVTVSS (SEQ ID NO:45) or a sequence having at least 90% sequence similarity thereto.

27. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDSTAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSRV ANLYPYWGQGTLVTVSS (SEQ ID NO:46) or a sequence having at least 90% sequence similarity thereto.

28. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASYRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:47) or a sequence having at least 90% sequence similarity thereto.

29. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGAYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:48) or a sequence having at least 90% sequence similarity thereto.

30. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDETYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:49) or a sequence having at least 90% sequence similarity thereto.

31. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDQTYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSK VADLYPYWGQGTLVTVSS (SEQ ID NO:50) or a sequence having at least 90% sequence similarity thereto.

32. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITAYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:51) or a sequence having at least 90% sequence similarity thereto.

33. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITEYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:52) or a sequence having at least 90% sequence similarity thereto.

34. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITQYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:53) or a sequence having at least 90% sequence similarity thereto.

35. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITSYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:54) or a sequence having at least 90% sequence similarity thereto.

36. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITTYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:55) or a sequence having at least 90% sequence similarity thereto.

37. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGKPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:56) or a sequence having at least 90% sequence similarity thereto.

38. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGQPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:57) or a sequence having at least 90% sequence similarity thereto.

39. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGSPLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:58) or a sequence having at least 90% sequence similarity thereto.

40. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRELITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:59) or a sequence having at least 90% sequence similarity thereto.

41. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRQLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:60) or a sequence having at least 90% sequence similarity thereto.

42. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRSLITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:61) or a sequence having at least 90% sequence similarity thereto.

43. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPEITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:62) or a sequence having at least 90% sequence similarity thereto.

44. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPGITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:63) or a sequence having at least 90% sequence similarity thereto.

45. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPQITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:64) or a sequence having at least 90% sequence similarity thereto.

46. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPTITSKV ADLYPYWGQGTLVTVSS (SEQ ID NO:65) or a sequence having at least 90% sequence similarity thereto.

47. A compound comprising an amino acid sequence of EVQLLESGGGLVQPGGSLRLSCAASGRYIDETAVAWFRQAPGKEREFVAGIGGG VDITYYADSVKGRFTISRDNSKNTLYLQMNSLRPEDTAVYYCAARPGRPLITEKV ADLYPYWGQGTLVTVSS (SEQ ID NO:66) or a sequence having at least 90% sequence similarity thereto.