What happened

Shares of Solid Biosciences (SLDB -2.62%) had crashed 31% lower as of 11:15 a.m. EDT on Tuesday. The company announced interim results from a phase 1/2 study of its gene therapy candidate SGT-001 in treating Duchenne muscular dystrophy (DMD) after the market close on Monday.

So those results were bad, right? Actually, no. Solid Biosciences called the data "encouraging," and at least one Wall Street analyst agreed. SVB Leerink's Joseph Schwartz upgraded the biotech stock to outperform from market perform and increased his one-year price target to $15, nearly 58% above Solid's closing price on Monday.

Man wearing a suit looking at a red line crashing through the floor

Image source: Getty Images.

So what

It's obvious that investors aren't convinced that Solid Biosciences has a winner on its hands with SGT-001, but the biotech's interim results did look pretty good.

Solid reported improvement for patients -- as measured by the North Star Ambulatory Assessment rating scale for the disease -- among all dose cohorts. Patients receiving SGT-001 also demonstrated improvement in the six-minute walk test, while the untreated control cohort showed a decline. In addition, patients in all dose cohorts receiving SGT-001 exhibited improvement in pulmonary function tests, while patients in the untreated control cohort had a mean decline of 10.7%.

The company also announced good news on the safety front. The six patients previously dosed with SGT-001 didn't have any new drug-related safety issues between 17 and 37 months after dosing. And the seventh patient in the study became the first to be dosed with a second-generation manufacturing process. This patient experienced only temporary and manageable adverse effects that weren't serious.

It could be that investors are concerned that Pfizer and Sarepta might beat Solid Biosciences. The two companies are currently evaluating experimental gene therapies targeting DMD and could announce results from pivotal studies sooner than Solid will.

Now what

Solid Biosciences will continue to dose patients in its phase 1/2 study of SGT-001. The company plans to report 90-day biopsy data from these additional patients in the second half of this year.