Shares of Achieve Life Sciences Inc (NASDAQ:ACHV) jumped over 50% at one point today, after the biotech company reported encouraging preliminary results from a Phase I/II study evaluating its lead drug candidates cytisine as a potential treatment for nicotine dependence.

Achieve Life Management Team

The study, initiated in October 2017, evaluated the repeat-dose PK and PD effects of 1.5mg and 3mg cytisine in 24 healthy volunteer smokers aged 18-65 years when administered over the standard 25-day course of treatment. The PK results indicated expected increases in plasma concentration between the standard and higher doses of cytisine with no evidence of drug accumulation. Smokers in the study were not required to have a designated or predetermined quit date, however, 58% of the subjects overall in the trial achieved biochemically verified smoking abstinence at day 26. Half (6/12) of the subjects on the 1.5mg arm and 67% (8/12) of the subjects on the 3.0mg arm achieved abstinence on day 26. Subjects who did not achieve abstinence had a significant reduction in number of daily cigarettes smoked by the end of treatment.

Cytisine was well-tolerated and reported adverse events were mostly mild and short-lived. Transient headache was the most commonly reported event, but was not treatment-limiting. No adverse events were severe, serious, or led to withdrawal from the study. Study results will be included in a clinical symposium on cytisine at the Society for Research on Nicotine and Tobacco (SRNT) Annual Meeting in Baltimore on Friday, February 23rd.

“The abstinence rates observed with cytisine are particularly impressive given the short 25-day treatment period. In addition, subjects did not commit to quitting and received only minimal behavioral support. Setting an actual quit date and receiving enhanced behavioral support are key factors to improve smoking cessation outcomes,” said Dr. Cindy Jacobs, Executive Vice President and Chief Medical Officer at Achieve. “We are encouraged by these results that further support our Phase 3 program that we expect to initiate mid-2018.”