Early research results on weight-loss drugs were disappointing. Roch (RHHBY.US) stock price fell nearly 5%.

Noticeably, Roche (RHHBY.US) shares fell on Thursday as a highly anticipated early-stage weight loss drug candidate from the company showed a high proportion of temporary side effects in preliminary human trials. After Roche disclosed details of the trial late on Wednesday, the company's stock dropped 4% when the European markets opened. A brief summary of the successful study in July had boosted the company's stock. According to a report presented at the European Association for the Study of Diabetes conference in Madrid, all 25 trial participants experienced mild to moderate side effects, or adverse events in industry terms, including those who only took an ineffective placebo. The side effects of the drug, known as CT-996, were mostly gastrointestinal (GI), similar to similar drugs. CT-996 was part of Roche's acquisition of Carmot for $2.7 billion last December. Analysts from Barclays and Jefferies Financial Group Inc. said that the high number of adverse events reflects similar data seen in Roche's early-stage weight loss drug development, data that has appeared in research from some pharmaceutical companies apart from Novo Nordisk A/S Sponsored ADR Class B and Eli Lilly. Jefferies Financial Group Inc. analysts stated: "We believe that given the higher-than-expected gastrointestinal side effects seen with both acquired assets, excitement for Roche's weight loss business may now need to take a pause." In terms of efficacy, Roche stated that obese non-diabetic patients who took CT-996 once daily saw an average weight reduction of 6.1% (adjusted for placebo) within four weeks. The company mentioned that the first stage of trials followed the convention of escalating drug doses through a process known as titration, which was faster than planned later-stage trials to quickly uncover any unforeseen side effects. Roche stated that the frequency of adverse events "is consistent with rapid titration and early development." The company said: "These data support further investigation of CT-996 in studies with longer duration, larger sample size, and slower titration rate."