Schrödinger is abandoning its CDC7 inhibitor after the therapy was linked to the deaths of two patients in a phase 1 leukemia trial.
The biotech had been evaluating the asset, dubbed SGR-2921, in an early-stage study of patients with relapsed/refractory acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes.
Schrödinger revealed in an Aug. 14 release that two of the patients with AML have died, with SGR-2921 “considered to have contributed” to the fatalities. The deaths, when considered alongside the drug’s “profile observed to date,” mean the biotech is discontinuing the program.
Biopharmas have been investigating the potential of inhibiting CDC7 for over 20 years, but none of these programs have made it into late-stage studies. When launching the phase 1 study, Schrödinger said that its digital platform had enabled the company to create SGR-2921, which it branded “the most potent CDC7 inhibitor reported to date and possess[ing] strong drug-like characteristics.”
The company had previously been expecting a readout from the trial in the final months of the year, having alluded to “early evidence of monotherapy activity” from the study. Executives had previously touted pharmacological data as suggesting that the CDC7 inhibitor had a “favorable, differentiated profile with best-in-class potential.”
While the initial strategy for SGR-2921 had included combining it with standard-of-care agents, the company said in this morning’s release that it now believes “the path to development as a combination therapy would be difficult to pursue.”
“Patient safety is our first priority, and in light of two treatment-related deaths in the phase 1 dose-escalation study, we have made the decision to discontinue further development of SGR-2921,” Schrödinger Chief Medical Officer Margaret Dugan, M.D., said in the release.
“While disappointing given the early clinical activity observed, we believe this is the right decision for patients,” Dugan added. “We had hoped to advance this investigational agent for acute myeloid leukemia as relapse rates are high, the disease progresses rapidly and there are limited therapies available.”
With SGR-2921 discarded, Schrödinger still has two other cancer drugs in the clinic, including a MALT1 inhibitor called SGR-1505 in a phase 1 study for relapsed/refractory B-cell lymphomas. There’s also SGR-3515, a Wee1/Myt1 inhibitor undergoing an early-stage study in patients with advanced solid tumors.