Healthy volunteers in Surrozen’s two phase 1 clinical trials have experienced treatment-related adverse events, leading to a voluntary pause on one study and some soul searching on the biotech’s financial resources and research priorities.
The voluntary enrollment pause for the early-stage trial of SZN-1326 was announced postmarket Monday as Surrozen issued third-quarter earnings. The biotech made the decision after elevated liver enzymes were noted in several subjects. Although the cases were asymptomatic, high levels of alanine transaminase and aspartate transaminase can signal liver damage. Surrozen said the elevations were listed as grade 3, but no serious adverse events were reported. The trial began in May.
None of the subjects experienced increases in total bilirubin, which can also signal liver or bile duct problems, and no changes in liver function were noted. Surrozen also said there were no other clinically significant laboratory anomalies seen. The transaminase elevations resolved spontaneously, the company added.
With the trial on hold, Surrozen plans to analyze the data so far with the study investigator and conduct preclinical experiments to try to figure out what led to the elevations. The company said this issue had not arisen in previous preclinical testing. Once that analysis is done, Surrozen will make a decision on the next steps for the SZN-1326 program.
Surrozen saw similar liver enzyme elevations in a phase 1 trial of the severe alcoholic hepatitis therapy SZN-043, also being studied in healthy volunteers at the moment. Dosing in the early-stage trial began in June.
The grade 1 and 2 asymptomatic liver transaminase elevations occurred in subjects who had been dosed with the drug. Again, there were no cases of elevated bilirubin or changes in liver function, and the situation resolved on its own. Surrozen said there were no serious adverse events reported. The company now plans to reconsider the development timeline for SZN-043 as a single ascending dose, which is the initial priority. The company hopes to expand the drug’s indication into other severe liver diseases.
“We will continue to analyze the data from the initial portion of our phase 1 studies, expand our pre-clinical research into the potential mechanisms of the observed adverse events and plot a course that reflects our commitment to patient safety and the potential for our technologies to address significant unmet medical need,” said CEO Craig Parker in the release. “Accordingly, we will be conducting a review of our financial resources and prioritization of our research pipeline.”
Meanwhile, Surrozen is working with Boehringer Ingelheim on the eye disease drug SZN-413. The two companies signed a deal worth $12.5 million upfront and a potential $586.5 million down the line in milestones back in October.
Surrozen had cash, cash equivalents and marketable securities of $78.4 million as of the end of the third quarter.