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Peptide YY (PYY) is a 36-amino acid endogenous gut hormone released from L-cells of the distal intestine in proportion to caloric intake.

Bivalirudin is a 20-amino acid synthetic direct thrombin inhibitor (DTI) derived from hirudin, the natural anticoagulant found in medicinal leech saliva.

Eptifibatide (Integrilin) is an FDA-approved cyclic heptapeptide antiplatelet agent derived from a disintegrin protein found in the venom of the southeastern pygmy rattlesnake.

Ganirelix is a synthetic decapeptide GnRH antagonist used in assisted reproductive technology to prevent premature LH surges and unintended ovulation during controlled ovarian hyperstimulation for IVF.

PACAP (Pituitary Adenylate Cyclase-Activating Polypeptide) is a highly conserved neuropeptide belonging to the VIP/secretin/glucagon superfamily.

Abaloparatide is a 34-amino acid synthetic analog of parathyroid hormone-related protein (PTHrP) approved by the FDA under the brand name Tymlos for treating osteoporosis in postmenopausal women and men at high fracture risk.

Angiotensin 1-7 is an endogenous heptapeptide produced from angiotensin II by angiotensin-converting enzyme 2 (ACE2).

Aviptadil (RLF-100) is a synthetic form of human vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide naturally produced throughout the lungs, gut, and nervous system.

Bortezomib (Velcade) is an FDA-approved first-in-class dipeptide boronic acid proteasome inhibitor used in the treatment of multiple myeloma and mantle cell lymphoma.

Calcitonin (Miacalcin) is an FDA-approved 32 amino acid polypeptide hormone used for the treatment of postmenopausal osteoporosis, Paget's disease of bone, and hypercalcemia.

Carfilzomib (Kyprolis) is an FDA-approved second-generation tetrapeptide epoxyketone proteasome inhibitor used for the treatment of relapsed or refractory multiple myeloma.

Cetrorelix is a synthetic decapeptide and gonadotropin-releasing hormone (GnRH) antagonist approved by the FDA under the brand name Cetrotide.

CGRP (Calcitonin Gene-Related Peptide) is a 37-amino acid neuropeptide produced by alternative splicing of the calcitonin gene.

Collagen Type II is the primary structural protein of articular cartilage, constituting the major fibrillar component of the cartilaginous ECM.

Cortexin is a polypeptide preparation extracted from the cerebral cortex of cattle, developed in part by the Khavinson research group and registered as a pharmaceutical drug in Russia since 1999.

Enfuvirtide (Fuzeon) is an FDA-approved 36 amino acid synthetic peptide that was the first HIV fusion inhibitor and the first of an entirely new class of antiretroviral drugs.

Glucagon is a 29-amino acid peptide hormone produced by pancreatic alpha cells and is the principal counterregulatory hormone to insulin.

Gonadorelin is a synthetic decapeptide identical in structure to endogenous gonadotropin-releasing hormone (GnRH), produced naturally by the hypothalamus.

Humanin is a 24-amino acid mitochondrial-derived peptide (MDP) encoded within the 16S ribosomal RNA gene of the mitochondrial genome.

Lanreotide (brand: Somatuline) is an FDA-approved synthetic octapeptide analog of somatostatin indicated for acromegaly, neuroendocrine tumors (NETs), and carcinoid syndrome.