By Gabriel Stargardter May 14 (Reuters) - Chinese biotech firm Kintor Pharmaceutical Limited saw its stock price jump by more than 20% the day after it announced on April 25 that it had "completed the first patient enrollment and dosing" in a late-stage U.S. clinical trial of its experimental COVID-19 treatment. It was the company's latest announcement about the progress of the drug, Proxalutamide. The Hong Kong-listed company's stock price has nearly quadrupled since March 1 as some analysts wrote about the big sales potential for a COVID-19 treatment. Kintor has seen its market capitalization soar to HK$23.4 billion ($3 billion) from HK$6.6 billion ($850 million) on March 1.