It's been tough to get what you want in the biotech initial public offering space this year - through April, the average take has been about $52 million, but most SEC filings show companies had hoped for much more.

Into this steps Trubion Pharmaceuticals Inc., of Seattle. While not yet setting a price range or number of shares, the company is anticipating an IPO of $86.25 million, making it one of five companies now on file seeking that amount or more.

By today's standards, $86.25 would be a very healthy IPO. Of the 12 completed IPOs this year, only one - Altus Pharmaceuticals Inc. - brought in anything close to that, selling 7 million shares at $15 apiece for $105 million. According to BioWorld Industry Snapshots, the other 11 IPOs completed on a U.S. market in 2006 each totaled less than $60 million, with most falling significantly below that amount. (See BioWorld Today, Jan. 27. 2006.)

How will Trubion fare? The company's platform, SMIP (Small Modular Immunopharmaceuticals), has produced two candidates for four indications - TRU-015 in rheumatoid arthritis and systemic lupus erythematosus (SLE), and TRU-016 in non-Hodgkin's lymphoma and chronic lymphocytic lymphoma. It has a whopper of a deal with Wyeth and proof-of-concept data for its lead drug. It raised $32 million in a Series B in July 2004 and as of March 31, had a cumulative deficit of just $42.1 million. That is not a bad package to bring to the public markets.

Jason Kantor, an analyst with New York-based RBC Capital Markets, acknowledged "most of the [IPOs] that get done have been downsized or have been reduced to make the IPO happen," but he pointed to Trubion's positive assets.

"One of the things that is driving interest in Trubion is a technology that looks very interesting," he told BioWorld Today. "But more importantly, it has an antibody that is in a very large space [CD20 target], and it has shown some interesting clinical data in man."

Kantor declined to speculate on the firm's chances at IPO, but he mentioned GlycoFi, of Lebanon, N.H., which is in the process of being bought by Merck and Co. Inc., of Whitehouse Station, N.J., for $400 million. GlycoFi has a promising technology, but "in terms of clinical candidates, it is just not there," and public market value lagged. Trubion has helped set itself apart with clinical data.

Trubion's drugs are single-chain polypeptides that are about one-half the size of therapeutic monoclonal antibodies. The company said they give better tissue penetration and improved therapeutic benefit. Given that antibody technologies have drawn M&A interest of late, it will be interesting to see what happens to Trubion.

The lead product, TRU-015, targets CD20 and is in a Phase IIa trial in RA that has completed enrollment. A Phase IIb is expected to start enrolling patients in the second half of the year. The product is being tested in SLE, too, but the company has not disclosed at what stage. Trubion also is developing it for an undisclosed niche indication, for which it has fast-track status and has reached Phase IIa, with a Phase II/III expected next year. Wyeth, of Madison, N.J., is the partner for TRU-015, although for the undisclosed indication, Trubion has retained co-promotion rights in the U.S.

TRU-016, which targets CD37, still is preclinical, with an investigational new drug filing anticipated for the second half of 2007. The product is unpartnered.

There is other preclinical work, and the company said in its prospectus its platform should allow it to bring one additional product candidate into clinical trials "in 2008 and each year thereafter."

That whopper Wyeth deal? It ranks as one of the largest of 2006, trailing only South San Francisco-based Exelixis Inc.'s deal with Daiichi Sankyo Co. Ltd., of Japan, which could total $1 billion in milestone payments. (See BioWorld Today, March 21, 2006.)

Trubion didn't miss the top spot by much, though. Wyeth paid $40 million up front in January, and if the IPO goes through, it would buy from Trubion in a private placement common stock equal to 20 percent of the number of shares sold in the IPO. Wyeth is paying for the ongoing development and commercialization of certain SMIP products and is on the hook for up to $250 million in milestone payments for CD20-directed therapies. It also would pay up to $535 million more in milestones for therapies directed to a fixed number of targets selected by Wyeth. There also are royalties involved, although Wyeth could terminate the agreement without cause at any time after Dec. 22, 2007. (See BioWorld Today, Jan. 4, 2006.)

The company said it had "no specific plans" for IPO proceeds, saying the offering is meant to create "a public market for our common stock" and would allow access to the markets in the future. If completed, the company would trade on Nasdaq under the symbol "TRBN."

Trubion's largest shareholders include ARCH Venture Partners, which holds 19.1 percent of the firm; Frazier Healthcare Ventures, with 18.2 percent; Oxford Bioscience Partners, with 17.8 percent; Prospect Venture Partners II LP, with 15.1 percent; and Venrock Associates, also with about 15.1 percent.