What’s happening: Molecular Partners, based in Schlieren, Switzerland, is taking out the red pen. The Swiss biotech company plans to cut up to 55 jobs, equivalent to around 44% of its workforce. The layoffs are due to be completed by the second quarter of 2027, although the full cost savings will only take effect in the second half of the year. Officially, the company attributes the move to a strategic focus on its Radio-DARPin pipeline. It seems likely, however, that its financial resources and constraints also play a significant role.
No new money in sight: As of September 30, Molecular Partners held cash and cash equivalents of CHF 57.5 million (around $69 million). Under its current plans, this should cover operating expenses and investments through the end of 2027. At the end of the first half, its cash balance had stood at CHF 67.9 million. Cash outflows therefore remain substantial. For the full year 2026, the company expects operating expenses of CHF 50 million to CHF 55 million.
One disclosure in the financial report is particularly revealing: Molecular Partners explicitly refers to a material uncertainty that could cast doubt on its ability to continue as a going concern. Since its last capital raise in October 2024, it has been unable to secure additional funding. Efforts to obtain further financing are continuing. The company lists a direct share offering or alternative financing structures as possible options. The job cuts are therefore more than a matter of strategic efficiency; they are also an attempt to preserve the remaining funds for the most promising programs for as long as possible.
The radiopharmaceuticals pipeline: The restructuring also marks a clear departure from the company’s previous breadth. Founded in 2004, Molecular Partners has built its own class of therapeutic molecules around so-called Designed Ankyrin Repeat Proteins (DARPins). These small, artificially designed proteins can bind to targets with high specificity and can be used as standalone therapeutics or as carriers for therapeutic payloads.
Radio-DARPins are now set to take center stage. These DARPin molecules deliver radioactive isotopes directly to tumor cells. The concept is broadly similar to other radioligands, such as Novartis’ Pluvicto, but uses a different vector technology. Molecular Partners is pursuing an isotope-independent approach in which different radioactive alpha emitters, such as lead-212 or actinium-225, can be combined with the respective targets.
CEO Patrick Amstutz bases the new direction on the initial clinical findings from lead candidate MP0712. “Encouraged by the emerging Phase 1/2a data from MP0712,” he said in the company’s Q3 results, the time was now right to focus on targeted radiotherapy. Clinical data in 2027 should show whether expectations are also borne out in terms of efficacy.
MP0712 targets DLL3, which is particularly relevant in small cell lung cancer (SCLC) and other neuroendocrine tumors. The candidate is being developed jointly with Orano Med and carries the alpha-emitting isotope lead-212. The US Phase 1/2a study has completed enrollment at the second dose level. Initial safety data are due to be presented in December 2026, with efficacy data announced for 2027. No dose-limiting toxicities have been observed at the first dose level so far; reported adverse events were mild to moderate.
Zoom in: Alongside MP0712, Molecular Partners has a second Radio-DARPin candidate, MP0726, in its pipeline. It targets mesothelin (MSLN), a molecule frequently found on tumor cells in ovarian cancer, among other cancers. An initial human imaging study is planned as the first step for MP0726.
Only on October 22, the company also selected MP0730 as the third candidate in its radiopharmaceutical pipeline. The drug candidate targets CD70, which is overexpressed in clear cell renal cell carcinoma, among other cancers. According to the company, preclinical studies in tumor-bearing mice showed pronounced and sustained accumulation in tumor tissue compared with healthy tissue. A first clinical study is scheduled to begin in mid-2027.
The big picture: The proximity of this announcement to the newly announced job cuts is striking. Molecular Partners presented the selection of MP0730 as a further expansion of its growing radiopharmaceutical pipeline. Just one week later, the company is announcing plans to dismiss up to 44% of its employees. For observers, this raises the question of how many development projects a substantially smaller organization can actually advance in parallel — or whether the workforce reduction will be followed by a narrowing of the pipeline.
Another DLL3 candidate, MP0714, is also being investigated through an early access program in South Africa. The Nuclear Medicine Research Infrastructure (NuMeRI) is working with the company on this program. The candidate is being used with different isotopes for imaging and treatment.
Also notable: The prioritization becomes even clearer when looking at the rest of the pipeline. Until now, Molecular Partners has also been developing so-called immune cell engagers, including multispecific T-cell engagers. These programs will no longer be central to its own development activities. Instead, the company intends to pursue the potential of its DARPin platforms, including Switch-DARPins, through strategic partnerships and possible spinouts.
These programs include MP0533, a tetravalent T-cell engager for acute myeloid leukemia (AML); MP0317, a FAP-targeted CD40 agonist; and the preclinical candidate MP0632, a logic-gated T-cell engager. Results from the completed dose-escalation phase of MP0533 are due to be presented at the ASH meeting in December. A Phase 2 study of MP0317 is ongoing, while new preclinical data have been announced for MP0632.
This does not mean these programs are being discontinued. Their further development, however, is expected to depend more heavily on external partners or independent spinouts. For Molecular Partners, this offers a way to preserve the value of the DARPin technology it has built over many years without having to bear all the necessary development costs itself.
What’s next: By concentrating on Radio-DARPins, Molecular Partners is betting on a field in which numerous biotech companies and pharmaceutical groups are currently positioning themselves. Combining precise tumor targeting with highly potent radiation is considered a promising approach, particularly for tumors that are difficult to treat. At the same time, the clinical development and manufacturing of these therapies are demanding. Additional requirements involve isotope supply, production logistics and the availability of nuclear medicine infrastructure.
With Orano Med, Molecular Partners has a partner that brings experience with alpha emitters. This gives the company access to important external expertise across the development chain. Nevertheless, its capital requirements remain substantial, particularly if several candidates are to enter clinical development in parallel.
The announced downsizing is therefore also likely to mean a reallocation of available resources. The initial focus will be on MP0712 and the further development of the two newer programs, MP0726 and MP0730. Whether all three actually advance within the announced timelines will depend, not least, on Molecular Partners’ ability to secure additional capital or further development partners.
The bottom line: The company’s message is this: fewer programs, with greater focus on a technology delivering its first encouraging clinical signals. The alternative reading is less comfortable: Molecular Partners must adjust its ambitions to the financial resources available. There is nothing particularly unusual about that in principle, but the central question remains whether an investor or pharmaceutical partner pursuing a radioligand strategy will choose to put its faith in this particular small, unsteady vessel. Only positive news in the near term will help restore confidence.
Sign up for our newsletter!
