** Shares of biotechnology co Hillstream BioPharma HILS.O
rise 38.9% to $1.07 premarket
** Stock among top performers across U.S. exchanges
** Co's board authorizes share repurchase program to acquire
up to $1 mln of its common stock urn:newsml:reuters.com:*:nGNX9dtbJ5
** As of March 31, co had approximately $11.1 mln in cash
and 11.4 mln shares of common stock outstanding
** Up to last close, stock down ~78% since January IPO
(Reporting by Mrinalika Roy in Bengaluru)
((mrinalika.roy@thomsonreuters.com; within U.S. +1 646 223
8780, outside U.S. +91 806749 8325;))