Shattuck Labs has terminated its CD47 program after weak efficacy data from its lead candidate, SL-172154, in blood cancer trials. The biotech reported only “modest” improvements in overall survival, prompting the company to shift its focus to other projects and cut 40% of its workforce.
Following the news, Shattuck’s shares dropped by 51% to $1.72 in premarket trading.
SL-172154, a dual-sided fusion protein designed to target cancer cells while minimizing side effects, was Shattuck’s leading candidate in acute myeloid leukemia (AML). However, disappointing trial results led the company to abandon the project. Median overall survival for patients receiving the treatment was 10.5 months, barely surpassing benchmarks for standard chemotherapy.
Shattuck CEO Taylor Schreiber stated that the company is now pivoting to its preclinical DR3 antagonist antibody, SL-325, aimed at treating inflammatory bowel disease. The biotech plans to begin human trials for the drug by Q3 2025.
The layoffs and restructuring, which will cost the company around $1.5 million, are expected to extend Shattuck’s cash runway into 2027. Additionally, Shattuck and Ono Pharmaceutical mutually agreed to terminate their partnership, ending potential milestone payments from the Japanese firm.
