ZURICH, Nov 5 (Reuters) - Relief Therapeutics and its private U.S. partner NeuroRx Inc. on Thursday pushed expectations for initial data from a clinical trial of a 50-year-old drug against COVID-19 to January, from this quarter as previously announced.

The announcement comes after a nearly 50% decline this week in the share price of the small Swiss company, according to Refinitiv data. The shares, trading at less than 1 Swiss franc, are still up significantly for the year.

Relief will continue the study of its drug RLF-100, also called aviptadil, against COVID-19 to its full enrolment of 165 patients after identifying no safety concerns, Relief and NeuroRx said in a statement, after a vote by its data monitoring committee on Wednesday to push ahead.

On Oct. 13, Relief and NeuroRx said results from the randomized, placebo-controlled study were expected "this quarter".

On Thursday, they said in a statement that "at current rates of enrolment (which may change as infection rates change) the study is expected to complete enrolment by mid-December and yield top-line data in January 2021."

"A couple of weeks after the end of the fourth quarter is what we're expecting right now," Jonathan Javitt, founder and chief executive of NeuroRx, said, telling Reuters that the new deadline reflects challenges in running a trial in the midst of a pandemic, including keeping staff safe.

Aviptadil, discovered a half century ago and studied over the years for a variety of uses including erectile dysfunction and pulmonary fibrosis, was part of Relief's portfolio when the COVID-19 pandemic began, prompting the company to seek to repurpose it. (Reporting by John Miller; Editing by Michael Shields)