Adds analyst comment in paragraph 6

By Sriparna Roy

April 22 (Reuters) - Bristol Myers Squibb BMY.N said on Tuesday its drug Cobenfy failed to show a statistically significant difference in a keenly watched late-stage trial that would help expand its use, sending its shares down nearly 5% in after-market trade.

The drug, which was approved last year, failed to meet the main goal in a trial that was testing Cobenfy in patients with schizophrenia who have stopped responding to their current antipsychotic treatments.

Bristol Myers obtained the drug, also known as KarXT, through its $14 billion takeover of Karuna Therapeutics, and is seen as one of the key growth drivers for the drugmaker. Wall Street analysts were eagerly awaiting the data from the trial as it would help accelerate the drug usage.

In the trial, the drug showed a two-point reduction on a scale that measures the symptom severity of the disease, compared to placebo, at 6 weeks.

At least two analysts, ahead of the results, said they were looking for mid-single-digit or greater improvement on the scale.

This marks a "blow for uptake curve," said William Blair analyst Matt Phipps, adding that it still is a large market opportunity.

The company was studying the drug as an adjunctive treatment to atypical antipsychotics in adults with schizophrenia, a mental health condition that affects how people think, feel and behave. It may result in a mix of hallucinations, delusions and disorganized thinking and behavior.

The trial enrolled adults aged 18 to 65 years with schizophrenia who were on stable background therapy at the time of enrollment.

Cobenfy targets cholinergic receptors as opposed to dopamine receptors, which have long been the standard of care.

There are currently no schizophrenia medications approved for use as an additional treatment to antipsychotics.

The drugmaker will complete a full evaluation of the trial data and intends to present detailed results at an upcoming medical conference.

(Reporting by Sriparna Roy in Bengaluru; Editing by Alan Barona)

((Sriparna.Roy@thomsonreuters.com))