NEW YORK (AP) — Japanese drugmaker Astellas Pharma Inc. said Friday a federal antitrust waiting period expired in regard to its $3.5 billion takeover bid for OSI Pharmaceuticals Inc.

The expiration satisfies a condition of the bid.

OSI, based in Melville, N.Y., has already rejected the $52 per share offer as too low. Astellas has attempted to acquire OSI for more than a year and, after repeated rejections, the Japanese company filed suit to prevent OSI's board from interfering.

Astellas made the hostile bid earlier this month.

OSI focuses on treatments for cancer, diabetes and obesity. It receives most of its revenue from the lung and pancreatic cancer drug Tarceva, which it sells in partnership with Genentech, which is now part of Roche.

Astellas has also given OSI a full slate of independent directors to consider at its annual stockholders' meeting. The nominees include Michael A. Griffith, the founder Aptuit Inc. and Jill Kanin-Lovers, who has served on the board of Alpharma Inc.

OSI has said the nominees' only mandate is to support the Astellas takeover.