Deep into the fall season, biotechs are freeing themselves of dead wood at a rapid pace. The latest batch of quarterly updates saw Atreca, aTyr Pharma, Histogen, Lisata Therapeutics, Poseida Therapeutics and Rain Therapeutics trim their pipelines.
Atreca has shed its EphA2-directed antibody drug conjugate (ADC) candidate ATRC-301 after seeing data from a nonhuman primate toxicity study. The study revealed safety signals, including bleeding, that led the biotech to stop development of an ADC it earmarked as its next clinical candidate in April. Atreca planned to file a request to begin human trials in the second half of next year but will now shift its attention to other molecules.
For aTyr Pharma, the decision to pull the plug on a planned phase 1 trial of ATYR2810 was driven by cash, not data. The candidate selectively blocks the NRP2/VEGFR signaling axis to sensitize aggressive cancers to chemotherapy. In disclosing the change in strategy, aTyr said its data “firmly” support the therapeutic potential of the molecule in rare aggressive tumors, but it needs to free up cash for its lead candidate efzofitimod.
Histogen is prioritizing its pipeline, too. With unresolved recruitment challenges blighting a clinical trial of HST-003 for for joint cartilage repair, Histogen is suspending all IND-enabling activities for its next program, HST-004. The biotech began human trial-enabling activities for the spinal disc repair candidate in the second quarter of last year but, with its cash pile down to $14.6 million, is now saving its money for other work.
Meanwhile, Lisata Therapeutics has suspended enrollment in its study of regenerative therapy Xowna after the trial failed to hit its recruitment targets. Blaming the COVID-19 pandemic and issues with the supply of catheters and a contrast agent, the biotech has decided to stop and run an interim analysis of six-month follow-up data on at least 20 patients. Lisata will only restart development if a strategic partner foots the bill.
Poseida has stopped enrollment in a phase 1 trial of solid tumor autologous CAR-T P-PSMA-101 in the belief that its allogeneic platform is the future. The candidate targets PSMA to treat prostate cancer and advanced salivary gland cancers. Poseida is continuing to collect data from the phase 1 trial to inform the development of its preclinical allogeneic candidate, P-PSMA-ALLO1.
Finally, Rain has deprioritized its phase 2 MANTRA-3 trial. The Merkel cell carcinoma study was part of Rain’s roster of trials of a small molecule inhibitor of the MDM2-p53 complex, but has been axed “to rationalize use of financial and personnel resources.” Rain took the action despite expecting its cash reserves, which were recently boosted by a $50 million offering, to last it into 2025.