Schrödinger is discontinuing the development of its blood cancer CDC7 inhibitor after two patient deaths.
In a Phase I trial (NCT05961839), SGR-2921 had originally shown activity as a monotherapy; however, the therapy was considered to have contributed to two deaths in patients with relapsed/refractory acute myeloid leukaemia (r/r AML). The trial also enrolled patients with high-risk myelodysplastic syndromes.
While these deaths were in patients treated with the drug as a monotherapy, Schrödinger also believes that the path to development as a combination therapy, the original intention, would be difficult to pursue.
Schrödinger CMO Dr Margaret Dugan said: “Patient safety is our first priority, and in light of two treatment-related deaths in the Phase I dose-escalation study, we have made the decision to discontinue further development of SGR-2921.
"While disappointing given the early clinical activity observed, we believe this is the right decision for patients. We had hoped to advance this investigational agent for AML as relapse rates are high, the disease progresses rapidly, and there are limited therapies available.”
The company’s stock opened 12.19% down, from a $19.84 close on 13 August to a $17.42 open on 14 August, shortly after the termination was confirmed.
Unmet needs in AML remain
There are several unmet needs in AML, especially in patients who experience relapse or do not achieve remission after initial treatment. Current therapeutic options are even more limited for AML patients with relapses.
In July 2025, Sellas Life Sciences’ CDK9 inhibitor SLS009 (tambiciclib), being used as a triple combination therapy, saw a mean overall response rate (ORR) of 33%, exceeding the threshold of 20%. ORR was the Phase Ia/II trial’s primary endpoint.
There are several therapies approved r/r AML, including Astella’s Xospata (gilteritinib), Agios Pharmaceuticals’ Tibsovo (ivosidenib) and Pfizer’s Mylotarg (gemtuzumab ozogamicin). However, all of these are for particular mutations of AML. AbbVie’s Venclexta (venetoclax) and hypomethylating agent (HMA) combinations are prescribed off-label in this patient population.
According to GlobalData, the AML market is set to reach $3.68bn in 2032, across the eight major markets (8MM: US, France, Germany, Italy, Spain, UK, Japan, and China).
GlobalData is the parent company of Clinical Trials Arena.


