Bicycle Therapeutics Plc

We are a clinical-stage pharmaceutical company developing a novel class of medicines, which we refer to as Bicycle molecules, for diseases that are underserved by existing therapeutics. Bicycle molecules are fully synthetic short peptides constrained to form two loops which stabilize their structural geometry. This constraint facilitates target binding with high affinity and selectivity, making Bicycle molecules attractive candidates for drug development. Bicycle molecules are a unique therapeutic modality combining the pharmacology usually associated with a biologic with the manufacturing and pharmacokinetic, or PK, properties of a small molecule. The relatively large surface area presented by Bicycle molecules allows targets to be drugged that have historically been intractable to non-biological approaches. Bicycle molecules are excreted by the kidney rather than the liver and have shown no significant signs of immunogenicity to date, qualities which we believe explain the molecules’ favorable toxicological profile.

We have a novel and proprietary phage display screening platform which we use to identify Bicycle molecules in an efficient manner. The platform initially displays linear peptides on the surface of engineered bacteriophages, or phages, before "on-phage" cyclization with a range of small molecule scaffolds which can confer differentiated physicochemical and structural properties. Our platform encodes quintillions of potential Bicycle molecules which can be screened to identify molecules for optimization to potential product candidates. We have used this powerful screening technology to identify our current portfolio of candidates in oncology and intend to use it in conjunction with our collaborators to seek to develop additional future candidates across a range of other disease areas.

Our internal programs are focused on oncology indications with high unmet medical need. Our product candidate, nuzefatide pevedotin, formerly BT5528, is a Bicycle Drug Conjugate, or a BDC molecule, whereby the Bicycle molecule is chemically attached to a toxin that, when administered, is cleaved from the Bicycle molecule and kills the tumor cells. We are evaluating nuzefatide pevedotin, a BDC molecule targeting Ephrin type A receptor 2, or EphA2, in both an ongoing company-sponsored Phase I/II clinical trial to assess safety, pharmacokinetics and clinical activity in patients with advanced solid tumors and an ongoing company-sponsored Phase II clinical trial to evaluate the efficacy, safety and pharmacokinetics of nuzefatide pevedotin in adult patients with recurrent metastatic pancreatic ductal adenocarcinoma after progression on a first-line therapy, which commenced recruiting patients in the first quarter of 2026. We are also developing BT1702, a Bicycle Radioconjugate, or BRC , molecule targeting Membrane Type 1 matrix metalloproteinase, or MT1-MMP, and carrying a lead-212, or 212 Pb, radioisotope payload for theranostic use. We are currently conducting Investigational New Drug application, or IND, -enabling activities for BT1702. We are also developing Bicycle Imaging Agents, or BIA molecules. In a BIA molecule, a Bicycle molecule is linked to a chelated radiopharmaceutical imaging agent. We are using BIA molecules to potentially derisk novel targets prior to further clinical development and to efficiently triage cancer indications for subsequent treatment with both BRC and BDC molecules. Our discovery pipeline in oncology includes next-generation BDC molecules, BRC molecules and BIA molecules.

Zelenectide pevedotin, a BDC molecule targeting Nectin-4, is being evaluated in an ongoing company-sponsored Phase I/II clinical trial to assess the safety, pharmacokinetics and clinical activity in patients with Nectin-4 expressing advanced malignancies, an ongoing Phase II/III registrational trial called Duravelo-2 evaluating zelenectide pevedotin in patients with untreated and previously treated metastatic urothelial cancer and in ongoing company-sponsored Phase I/II clinical trials to assess the efficacy and safety of zelenectide pevedotin in patients with NECTIN4 amplified advanced breast cancer and NECTIN4 amplified advanced or metastatic non-small cell lung cancer, which commenced recruiting patients in the first and third quarters of 2025, respectively. In March 2026, we announced the strategic reprioritization of our clinical portfolio to focus on our promising pipeline of next-generation therapeutics, including nuzefatide pevedotin as well as next-generation Bicycle conjugates, including BRC molecules. While dose selection data from the clinical trial for zelenectide pevedotin are promising, demonstrating response rates comparable to published rates for existing standards of care and a differentiated safety profile, we plan to convert the Phase II/III Duravelo-2 registrational trial to a randomized Phase II clinical trial and deprioritize the program for internal development while we evaluate next steps for zelenectide pevedotin following preliminary feedback from regulatory agencies. In addition, as part of the strategic reprioritization, we plan to discontinue the Phase I/II clinical trials evaluating zelenectide pevedotin in patients with NECTIN4 amplified advanced breast cancer and NECTIN4 amplified