Mealey's (January 21, 2020, 2:08 PM EST) -- SAN FRANCISCO — The California federal judge overseeing the Viagra/Cialis melanoma multidistrict litigation on Jan. 13 allowed plaintiffs to present expert testimony that it is biologically plausible for the erectile dysfunction drugs to cause progression of melanoma, but he granted a defendants’ motion to exclude opinions on general causation (In Re: Viagra and Cialis Products Liability Litigation, No. 16-md-2691, N.D. Calif., 2020 U.S. Dist. LEXIS 7216)....