HEALTH CARE

Top Researcher at Genentech Resigns: Franz Hefti, its director of neuroscience, will leave at the end of August, dealing a new blow to Genentech Inc. research efforts. He will head Merck & Co.’s 300-person neuroscience institute in London. Merck, a drug company, is based in Whitehouse Station, N.J. Hefti had been discussing leaving the South San Francisco-based biotechnology company since early May, a company spokesman said. Genentech said Hefti’s resignation was not related to the company’s ouster Sunday of its president and chief executive, G. Kirk Raab. The spokesman noted that Hefti told the company of his departure plans June 14, a week before the company’s board started the inquiry that led to Raab’s dismissal. Genentech stock closed at $47.875, down 25 cents a share, on the New York Stock Exchange.