* Aronex Pharmaceuticals Inc., of The Woodlands, Texas, signed a licensing agreement for development of its antibody-toxin complex, AR209, with Boehringer Mannheim GmbH, of Mannheim, Germany, for treatment of cancer. The drug is a combination of an antibody that binds to the oncoprotein erbB-2, which is expressed on the surface of cancer cells, and a Pseudomonas exotoxin to kill the tumor cells.

* Arqule Inc., of Medford, Mass., and Signal Pharmaceuticals Inc., of San Diego, expanded their collaboration for discovery of small molecule compounds that modulate gene expression. Financial terms were not disclosed.

* Avid Corp., of Camden, N.J., said it licensed from DuPont Merck Pharmaceutical Co., of Wilmington, Del. a second generation HIV protease inhibitor. Financial terms were not disclosed. Avid said it expects to begin clinical trials with the AIDS drug within the next several months. DuPont Merck is a joint venture of E.I. DuPont Co., of Wilmington, and Merck & Co., of Whitehouse Station, N.J.

* Bio-Technology General Corp., of Iselin, N.J., submitted a new drug application with the FDA for a testosterone product, Androtest-SL, for treatment of hypogonadism. The testosterone replacement therapy is administered under the tongue rather than through injections or skin patches.

* Neose Technologies Inc., of Horsham, Pa., registered with the Securities and Exchange Commission for a follow-on offering of 1.25 million shares. The company (NASDAQ:NTEC) went public in February, raising $32 million in gross proceeds through the sale of about 2.59 million shares at $12.50.