AdipotidevsVK2735

Adipotide uses a fundamentally different approach to fat reduction compared to appetite suppressants or metabolic modulators — it physically destroys the blood supply feeding white adipose tissue. The molecule is a chimeric peptidomimetic with two functional domains: a targeting peptide (sequence CKGGRAKDC) that homes to blood vessels in white fat, and a pro-apoptotic peptide (D(KLAKLAK)2) that kills the cells it enters.

The targeting sequence binds specifically to prohibitin, a protein expressed on the luminal surface of endothelial cells in the vasculature supplying white adipose tissue but not other organ systems. This vascular address system means adipotide accumulates selectively in fat tissue blood vessels. Once bound, the molecule is internalized into the endothelial cells, where the pro-apoptotic D(KLAKLAK)2 domain disrupts mitochondrial membrane integrity, triggering programmed cell death.

As the blood vessels supplying fat deposits are destroyed, the adipose tissue they serve undergoes ischemic cell death and is gradually reabsorbed by the body. In rhesus monkey studies, adipotide treatment produced significant reductions in body weight and waist circumference, with measurable decreases in white fat mass on imaging. However, the approach carries inherent risks — the targeting is not perfectly specific, and prohibitin expression in renal vasculature led to significant kidney toxicity in primate studies, which has severely limited clinical development.

VK2735 is a once-weekly subcutaneous dual GLP-1/GIP receptor agonist with a structure optimised for high potency and a clean tolerability profile. Dual incretin receptor activation produces complementary effects on appetite, glucose handling, and energy expenditure: GLP-1 receptor agonism delivers central appetite suppression through hypothalamic arcuate-nucleus signalling, slows gastric emptying, and triggers glucose-dependent insulin secretion, while GIP receptor activation amplifies the insulin response, supports beta-cell function, and modulates adipose tissue lipid handling.

The molecule's pharmacokinetic profile delivers sustained receptor exposure across a one-week dosing interval, achieved through structural modifications that enable albumin binding and resistance to proteolytic degradation. In the Phase 2 VENTURE trial, the 15 mg dose produced 14.7% mean body weight loss at 13 weeks — the fastest early weight loss observed for any obesity drug, with the loss curve still descending steeply at trial end. This rapid trajectory suggests substantially greater total weight loss would be achievable with longer dosing, and Phase 3 VANQUISH trials launched in 2026 are testing 68-week treatment durations to characterise the full magnitude of effect.

Viking is also developing an oral tablet formulation of VK2735 in parallel, which entered Phase 1 in 2024-2025. If both formulations succeed, Viking would have one of the most flexible GLP-1/GIP product profiles on the market — though as a small biotech company it faces significant manufacturing and commercial scaling challenges relative to Lilly and Novo Nordisk.