UK biotech Tiziana Life Sciences Plc /zigman2/quotes/207307745/composite TLSA +1.32% said Wednesday its TZLS-501 treatment could be used for patients with the coronavirus that causes COVID-19 and are at risk of respiratory failure. The company is accelerating development of the treatment with Novimmune SA, a Swiss biotech company. "Tests have already shown that the treatment rapidly depletes circulating levels of IL-6 in the blood," the company said in a statement. "An excessive production of IL-6 is regarded as a key driver of chronic inflammation and is believed to be associated with severe lung damage observed with COVID-19 infections and acute respiratory illness." Shares were up more than 300% premarket. The stocks of many small biotechs and medical device companies that have made announcements relating to the virus have rallied hard as the illness has spread around the world, even though experts caution it will take a long time to develop treatments.