Syros Pharmaceuticals’ blood cancer prospect tamibarotene has failed another study, triggering a default on a loan and wiping 85% off the share price of the beleaguered biotech.
The phase 3 trial was assessing the effect of using the retinoic acid receptor alpha agonist tamibarotene in combination with azacitidine in newly diagnosed, higher-risk myelodysplastic syndrome (MDS) patients. Syros saw a 23.8% complete response rate in people who received the combination, compared to 18.8% in patients who received placebo on top of azacitidine.
The difference between the response rates fell short of statistical significance, causing the trial to miss its primary endpoint. Syros is stopping the study and reviewing the full data set to inform the next steps. The response rate in the control cohort is in line with historical data on azacitidine.
Investors, already burnt by setbacks such as a recent acute myeloid leukemia flop, sent Syros’ share price down 85% to below $0.40 in the aftermath of the readout.
The response may reflect both the big blow to the prospects of tamibarotene and the potential financial implications of the failure.
Under the terms of an agreement signed in 2020, the failure of the MDS trial to hit its primary endpoint constitutes an event of default. The default allows the lender, Oxford Finance, to declare all obligations under the loan agreement immediately due and payable. Syros said the repayment of $43.6 million may be accelerated as a result of the default. The biotech ended September with $58.3 million.
Late last month, Syros forecast the sum would fund operations into the third quarter of 2025 and allow it to prepare an application for FDA approval based on the MDS data. However, the phase 3 failure has put the future of tamibarotene—and Syros—in doubt.