Additional data released from a U.S. Phase III trial of thymosin alpha1 for hepatitis B, while not statistically significant, is moreencouraging than the initial results released a year ago that suggestedthe drug and placebo had equal effects.SciClone Pharmaceuticals Inc., of San Mateo, Calif., took over rightsto the study from former licenser Alpha 1 Biomedicals Inc. inNovember. On April 28, 1994, Alpha 1 said the 99-patient trialshowed about equal response between the drug and placebo as itrelated to clearance of hepatitis B virus (HBV) DNA.The additional data released Monday concerned clearance ofhepatitis e antigen in addition to HBV DNA. The study, done at threeU.S. centers, showed 12 of 49 patients (25 percent) treated with thedrug, called Zadaxin, had sustained elimination of both indicatorsduring the one-year study or in the follow-up period. Six of 48 (13percent) in the placebo group had remission of the disease.Thomas Moore, SciClone's chairman and CEO, told BioWorld theresults are more in line with what the company has seen in otherstudies, and should help with regulatory filings around the world."The announcement of incomplete data one year ago led some to apremature conclusion that Zadaxin had no greater effect on chronichepatitis B than placebo," Moore said. "It's significantly better thanthe world believed it was. But it still doesn't show as good a responseas a number of other controlled trials that have been run with thedrug."After the Alpha 1 announcement, the stock prices of SciClone(NASDAQ:SCLN) and Alpha 1 fell 59 and 68 percent to $5.19 and$2 per share, respectively. SciClone's stock closed up 13 centsMonday at $6.13.Moore said he expects that many people still will be skeptical of thedrug until more positive data is forthcoming. That could come, hesaid, from an ongoing 158-patient trial in Taiwan, which is notblinded.Biotechnology analyst, Brandon Fradd, with Montgomery Securitiesin San Francisco, agreed that it "probably will take some verycompelling results for people to re-evaluate their opinions." ButFradd already believes in Zadaxin's benefit."Now it looks fine," he said of the U.S. trial data. "It's consistentwith what they're seeing in Taiwan and Italy. Compared to notherapy or placebo therapy, this product produces statisticallysignificant results."Fradd said the U.S. results lacked significance only because of thesample size, and said that statistically significant results might beseen this summer in the Taiwan trial.SciClone has been releasing data periodically from the Taiwan trialthat has shown encouraging trends.SciClone has approval to market the drug in Singapore but is waitingto launch there until more data is available from Taiwan, since thenegative publicity from the U.S. trial last year reached Singapore andother markets. Moore said SciClone wants to be sure physicians arecomfortable with the drug and its benefits.Detailed results of the U.S. trial will be presented May 14 at theDigestive Disease Week meeting in San Diego. An abstract from trialinvestigators is being run in the May issue of Gastroenterology.SciClone pooled data from five trials of Zadaxin in chronic hepatitisB, involving 207 patients. Together there was a 35 percent responserate in the treated groups compared to 20 percent in the control group(one trial used interferon alpha as control). Moore said the companyintends to get an independent analysis of results that will take intoaccount the variables, such as endpoints and treatment duration, so afair assessment can be made. n

-- Jim Shrine

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