MannKind Corp., a Valencia biopharmaceutical company that develops therapeutic products for diseases such as diabetes and cancer, was one of the week’s leading gainers. Shares rose 50 percent to close at $2 on Friday.

Capricor Therapeutics Inc. was also a big gainer this week. Shares of the Beverly Hills biopharmaceutical firm rose 20 percent to close the week at $2.60.

Ritter Pharmaceuticals Inc., which focuses on therapeutics for gastrointestinal diseases, was among the week’s losing stocks. Shares for the Century City firm fell 26 percent to close the week at $1.32.