Bicycle Therapeutics is a clinical-stage UK biotech developing a novel class of drug molecules — called "Bicycle molecules" — for cancer treatment. Bicycle molecules are short, fully synthetic peptides constrained into a double-loop structure, designed to combine the manufacturability of small molecules with the target-binding selectivity of biologics. The company's lead application is the Bicycle Drug Conjugate (BDC), which links a Bicycle molecule to a cytotoxin that is released in the tumor's extracellular space upon reaching the target antigen. Bicycle Therapeutics argues BDCs offer advantages over antibody-drug conjugates (ADCs) — a well-established cancer drug class — including faster tumor penetration, shorter systemic half-life, and a broader range of targetable antigens. The company's lead program, nuzefatide pevedotin, targets EphA2, a receptor overexpressed in several solid tumors including pancreatic and urothelial cancers. Bicycle Therapeutics also has an emerging radiopharmaceutical pipeline, led by BT1702, a molecule carrying an alpha-particle radioisotope payload targeting MT1-MMP, with a first clinical trial targeted for 2027. The company has no approved products and generates no product revenue, funded instead by cash on hand and collaboration agreements with Ionis and Bayer. Following a March 2026 strategic reprioritization — including a roughly 30% workforce reduction — Bicycle Therapeutics is narrowing its focus to nuzefatide pevedotin and its radiopharmaceutical pipeline, while seeking partners for deprioritized assets.