(Corrects to show patients were treated with SNA-001 before laser therapy, not after, in the second paragraph)
July 30 (Reuters) - Sienna Biopharmaceuticals Inc said on Monday two pivotal trials testing its lead experimental treatment for acne did not meet their main goals, sending its shares tumbling nearly 28 percent before the bell.
The topical treatment, SNA-001, when administered before laser therapy to patients with moderate-to-severe acne vulgaris did not show an additional benefit in reducing inflammatory lesions, when compared to those on the control arm of the study, the company said.
“We are disappointed by these results, which did not confirm the findings from the previous proof of concept study,” Chief Executive Officer Frederick Beddingfield said in a statement.
Results from a third acne trial are expected in the fourth quarter of 2018, with the treatment being separately tested as a therapy to reduce unwanted light-pigmented hair, the company said.
Shares of Sienna, which went public about a year ago, were down 22.9 percent at $12.11 in premarket trading. (Reporting by Tamara Mathias in Bengaluru; Editing by Shailesh Kuber and Anil D’Silva)