NEW YORK (Reuters) - The tumble in share prices for biotechnology stocks has created some buying opportunities, with drugmakers Celgene Corp (>> Celgene Corporation) and Gilead Sciences (>> Gilead Sciences, Inc.) poised for a 30 percent rise over the next year, Barron's said.

Both companies currently rely on closely related medications for the bulk of their income, creating risk, but the potential for diversification either through developing new treatments or being bought out could provide substantial upside, the publication said.

Celgene, which specializes in treatments for a blood plasma cell cancer called myeloma, could see double-digit growth for its Revlimid drug for years to come, with significant growth potential from overseas, Barron's said.

Despite negative publicity related to high prices on its hepatitis-C drugs, Gilead Sciences' products often cure patients within months, the publication said.

"That word, cure, isn't used often enough by Big Pharma," Barron's said.

The company also expects to generate $85 billion in cumulative free cash through 2020, which the publication said it could use to buy new medicines or repurchase shares.

(Reporting By Luc Cohen; Editing by Sandra Maler)

Stocks treated in this article : Gilead Sciences, Inc., Celgene Corporation