What happened

Sutro Biopharma (NASDAQ:STRO) was a rock star stock on Friday, with a mighty price increase on the back of some very good news released on Thursday. The company's STRO-002 cancer drug candidate showed impressive results in an early-phase clinical study involving patients with ovarian cancer.

So what

Updated data from the phase 1 clinical trial of STRO-002 showed that of the 31 evaluable participants, 23 reached disease control after 12 weeks, with 18 doing so after 16 weeks. Ten patients met response evaluation criteria in solid tumors (RECIST), a measurement of tumor development gauging how a cancer patient responds to a certain treatment criteria. The drug was well-tolerated by participants in the trial.

Cancer cells attacking a healthy cell.

Image source: Getty Images.

"We are seeing improved outcomes in disease control and RECIST responses as the data matures and [we] will continue to follow the patients who remain on study for further deepening of responses or clinical benefit," according to Sutro's Chief Medical Officer Arturo Molina. 

The patients in the study were all heavily pre-treated. Molina said that new patients coming in to the trials will be less so. He added that an expansion cohort for endometrial (lining of the uterus) cancer should be added next year.

Now what

An advance in the fight against any form of cancer is excellent news, given the disease's ubiquity. While these results are highly encouraging for Sutro, and the bullishness on the stock is deserved,  we should be cautious because they are drawn from a limited early-stage trial being conducted by the biotech.

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