Merck & Co. announced a major reshuffling of its top management yesterday, but biotechnology companies working with Merck said the change would not affect their operations or their relations with the pharmaceutical giant.

The reorganization, which was approved by Merck's board yesterday and will take effect next Monday, is intended to recognize the global nature of the pharmaceutical industry, according to P. Roy Vagelos, chairman and chief executive officer of the company. Merck has facilities in 18 countries, including Australia, Canada, Costa Rica, Ecuador, England, France, Germany, Japan, Mexico, Pakistan and Portugal, as well as the United States.

In the move, Merck pulled its worldwide human health prescription pharmaceutical business into a single division. The new Merck Human Health Division (MHHD), responsible for marketing Merck's prescription drugs, has been formed by consolidating the former Merck Sharp & Dohme and Merck Sharp & Dohme International divisions. Richard Markham has been elected president of MHHD and senior vice president of the company.

Merck also consolidated its global vaccine business in a new Merck Vaccine Division. Collaborative research programs with Repligen Corp. of Cambridge, Mass., to develop an AIDS vaccine and an HIV therapeutic come under its auspices. Dr. R. Gordon Douglas will become president of the Vaccine Division, reporting to Jerry T. Jackson, who with Markham is one of four new senior vice presidents.

Jackson also has responsibility for Merck's animal health and agricultural business, specialty chemicals, the consumer health care group and Merck's strategic alliance with Du Pont.

The changes at Merck are not expected to affect the joint research with Repligen, according to Ramesh L. Ratan, Repligen's senior vice president and chief financial officer. Merck has sunk $20 million into the research since its inception in 1987, he added.

Chiron Corp. of Emeryville, Calif., which receives royalty payments from Merck on the worldwide sales of hepatitis B vaccine, also does not expect to be affected by the changes, a company representative said.

By reorganizing, Merck also hopes to improve the management of the company's strategic alliances, Vagelos said. Merck formed a joint venture with Johnson & Johnson, called the Johnson & Johnson Consumer Pharmaceutical Co., in 1989; and last January it formed the Du Pont-Merck Pharmaceutical Company with Du Pont.

-- Rachel Nowak Washington Bureau Chief

(c) 1997 American Health Consultants. All rights reserved.