Key Highlights

  • Molecular Partners is deepening its focus on targeted radiotherapy and pivoting to become a dedicated radiopharmaceuticals company, led by lead asset MP0712, a DLL3-targeting Radio-DARPin with a 212Pb payload for SCLC.
  • The company plans to reduce its workforce by up to 55 positions, or approximately 44% of headcount, with implementation expected by Q2 2027 and full cost impact in H2 2027.
  • Dosing in dose level 2 (105 MBq) of the MP0712 Phase 1/2a US multicenter study is ongoing; initial safety data will be presented at NACLC in December 2026 and efficacy data are expected in 2027.
  • Cash and equivalents stood at CHF 57.5 million (~USD 69 million) as of September 30, 2026, expected to fund operations into late 2027.

Molecular Partners AG (NASDAQ:MOLN), the Swiss clinical-stage biotech developing DARPin miniprotein therapeutics, used its third-quarter 2026 update to formalize what has been an evolving strategy: the company is narrowing its entire focus to radiopharmaceuticals and is restructuring its organization to match. The announcement pairs a clear scientific rationale — driven by emerging Phase 1/2a data from its lead Radio-DARPin candidate MP0712 in small cell lung cancer — with a workforce reduction of up to 55 positions, representing up to 44% of current headcount. The moves signal that Molecular Partners is no longer hedging between multiple therapeutic modalities.

MP0712 Dose Level 2 Progressing; Safety Data Coming in December

MP0712 targets delta-like ligand 3, a protein overexpressed in small cell lung cancer and other neuroendocrine tumors. It is armed with bismuth-212, an alpha-emitting radioisotope, and is being co-developed with Orano Med, a specialist in 212Pb-based targeted Alpha therapies. The US multicenter Phase 1/2a study (NCT07278479) is progressing in dose level 2, set at 105 MBq per dose, which has been fully recruited. Eight of nine planned sites have opened.

All patients in dose level 1, dosed at 75 MBq, passed the safety observation window without any dose-limiting events. All adverse events through that level were mild to moderate — grade 1 or 2 — and transient, resolving in time for the next scheduled dosing cycle. Initial safety data from the trial will be presented at the International Association for the Study of Lung Cancer and American Society of Clinical Oncology North America Conference on Lung Cancer in December 2026. Efficacy data are expected in 2027.

Pipeline Expands While Organisation Streamlines

Beyond MP0712, Molecular Partners is advancing a pipeline of Radio-DARPin programs using an isotope-agnostic strategy that allows the DARPin vector to carry different alpha-emitting payloads, including both 212Pb and actinium-225. MP0714, a DLL3-targeting candidate labeled with 177Lu and 225Ac respectively, has entered an early-access clinical program in South Africa under a compassionate care framework administered by the Nuclear Medicine Research Infrastructure. Separately, the company's mesothelin-targeting candidate MP0726 is advancing toward first-in-human imaging in the second half of 2026. A third candidate, MP0730, targeting CD70, was nominated to the pipeline in October 2026 after preclinical data showed favorable tumor uptake relative to healthy tissues. Its first-in-human program is anticipated to start in mid 2027.

The restructuring — with formal consultation of affected employees underway under Swiss employment law — is expected to reduce headcount by up to 55 positions by Q2 2027, with the full cost reduction effective early H2 2027. Molecular Partners said the financial impact of severance and restructuring charges cannot be estimated yet and will be disclosed with full-year 2026 results in early 2027. Switch-DARPin and immune cell engager programs, including the FAP-targeted CD40 agonist MP0317 and the T cell engager MP0632, will continue to be explored through strategic partnerships and potential spin-out structures rather than direct internal development.

Cash Runway Into Late 2027 With Updated Cost Guidance

The company reported CHF 57.5 million, equivalent to approximately USD 69 million, in cash and equivalents at September 30, 2026. Under current operating assumptions, that cash is expected to fund operations into late 2027. For the full year 2026, Molecular Partners updated its total Operating Expense guidance to CHF 50 to 55 million at constant exchange rates, inclusive of approximately CHF 5 million of non-cash items related to share-based payments, IFRS pension accounting, and depreciation. The restructuring charges are excluded from that guidance as the quantum is not yet determined.

Molecular Partners is making a deliberate bet that DARPin miniproteins can anchor a competitive radiopharmaceuticals franchise, starting with an indication — small cell lung cancer — where response rates with existing therapies remain limited and the DLL3 target is well characterized. The December safety data readout from MP0712 will be the next signal investors can judge, followed by efficacy data in 2027 that will tell the story of whether the alpha-emitting payload and patient selection can translate the preclinical rationale into clinical benefit.