Just two months after appointing a new leadership team, Biomira Inc. expanded its oncology pipeline by acquiring Tucson, Ariz.-based ProlX Pharmaceuticals Corp.
Following the close of the deal, Biomira will pay out $3 million cash and about 17.9 million shares of common stock. Using Monday's closing price of $1.17, the shares are valued at about $21 million. The stock closed at (NASDAQ:BIOM) $1.26 Tuesday, up 9 cents.
Additionally, Biomira would pay $15 million in milestones tied to the first Phase III trial initiation and major regulatory approval of a ProlX product. ProlX shareholders also may share in any revenues resulting from a potential collaboration agreement in a non-oncology indication, the details of which have not been disclosed.
"When [chairman] Chris Henney and I joined the company, we set out deliberately to expand the pipeline in oncology beyond cancer vaccines," said Robert Kirkman, president and CEO of Biomira. "This is essentially a new company with new leadership and a new range of products."
Kirkman joined the Edmonton, Alberta-based company in August, the same month that Henney was named chairman. Kirkman said the ProlX introduction came through Philadelphia-based brokerage firm Janney Montgomery Scott LLC, which had been retained to help Biomira explore in-licensing options.
Although the acquisition gives Biomira a new clinical candidate and several preclinical programs, Stimuvax is the crown jewel of the pipeline. The internally developed, synthetic MUC1 peptide vaccine is slated to begin a Phase III trial in Stage III non-small-cell lung cancer (NSCLC) before the end of the year. The trial and subsequent commercialization will be handled by partner Merck KGaA, of Darmstadt, Germany, with Biomira receiving royalties.
Stimuvax uses a 25-amino acid sequence of the cancer-associated MUC1 mucin gene to stimulate an immune response to cancer. The peptide is encapsulated in a liposomal delivery system to enhance recognition of the cancer antigen by the immune system and facilitate delivery. In a Phase IIb trial, a pre-stratified subset of patients with locoregional Stage IIIB NSCLC demonstrated median survival of 30.6 months when treated with the vaccine, compared to 13.3 months with the control.
Biomira's new No. 2 compound is now ProlX's PX-12, which is being evaluated in a Phase Ib trial in patients with advanced gastrointestinal cancers. PX-12 inhibits thioredoxin, a protein that is overexpressed in cancer cells and has been linked to the aggressive proliferation of solid tumors, including colon, lung and gastric cancers. The compound is the "first thioredoxin inhibitor in the clinic," said ProlX president and CEO Lynn Kirkpatrick, who will join Biomira as chief scientific officer.
In a Phase I study, PX-12 was well tolerated and produced a decrease in plasma concentrations of thioredoxin that significantly correlated with increased patient survival. A Phase II trial in advanced pancreatic cancer is scheduled to begin before the end of the year, and enrollment of the targeted 80 patients is estimated to take 12 to 18 months.
Next to enter clinical trials will be ProlX's PX-478, another first-in-class compound. PX-478 inhibits hypoxia inducible factor-1a (HIF-1a), a protein involved in angiogenesis, and is the first direct inhibitor of the protein to be described. In preclinical studies, the compound demonstrated tumor regressions and growth inhibition in models of several solid tumors, and clinical trials are expected to start in the first half of 2007.
Biomira plans to advance another preclinical candidate into humans in 2007, and it now has several programs to choose from. Its own pipeline contains BGLP-40, a derivative of Stimuvax with a slightly modified antigen, and ProlX's pipeline includes PI-3-kinase inhibitor PX-866 and the Akt-mediated survival signaling inhibitor PX-316.
Last month, Biomira filed a $100 million shelf registration statement in the U.S. and Canada, which Kirkman said will be used opportunistically to fund the recently acquired pipeline. He declined to speculate regarding additional acquisitions and said the company currently is focused on "integrating and assimilating" the ProlX assets, but acknowledged he would be willing to look at "appropriate opportunities."