By Debbie Strickland

A $100 million big pharma deal and a high-profile DNA-based AIDS vaccine program weren't quite enough to carry Apollon Inc.'s initial public offering (IPO).

The Centocor spin-off proposed the IPO in October 1997 and amended it as late as Dec. 15, but opted to withdraw the $30 million offering last week.

"We decided to withdraw because of market conditions, and we're evaluating alternatives," said Vincent Zurawski, president and CEO, who declined further comment, citing quiet period restrictions.

An open question is how Apollon will fund its ambitious clinical program, which has taken eight genetically engineered Genevax vaccines to Phase I/II trials. Apollon expects to begin Phase II trials of herpes, hepatitis and HIV vaccines within the next 12 to 14 months.

As of Sept. 30, 1997, Apollon had $1.75 million in cash, following a nine-month net loss of $9 million.

The IPO financing would have funded operations through mid-1999.

Apollon is based in Malvern, Pa., as is its parent firm, Centocor Inc., which owns about one-third of Apollon. Centocor's stake would have dropped to below 25 percent had Apollon's 2.5 million-share offering succeeded. The shares were expected to price between $11 and $13 each.

The company claims to have been the first to launch clinical trials of DNA-based therapeutic and preventive vaccines for HIV, and the first to bring to trial a therapeutic vaccine against herpes simplex virus.

The vaccine products link DNA to a facilitating agent, such as bupivacaine, a local anesthetic. The components directly interact with each other to form small enclosed vesicles containing DNA. (See BioWorld Today, April 29, 1997, p. 1.)

In October 1995, the company agreed to collaborate on AIDS and herpes simplex virus vaccines with Wyeth-Ayerst Laboratories, in a deal worth up to $100 million. Wyeth-Ayerst is a Radnor, Pa.-headquartered division of American Home Products Corp, of Madison, N.J.

As of Sept. 30, Apollon had received $15.1 million from its centerpiece partnership. *