BioWorld International Correspondent

LONDON - Protherics plc announced a placing and open offer to raise £10 million (US$18.6 million) to build U.S. and European sales forces for Voraxaze, a treatment for methotrexate toxicity, which it intends to submit for approval later this year.

The Runcorn, UK-based company is issuing 20.8 million shares at 48 pence per share, a 6.8 percent discount to Monday's closing price, on the basis of one new share for every 10 existing shares. The deal is fully underwritten.

Voraxaze has orphan drug status in the U.S. and Europe, and approval is expected before the end of 2005. The product already is available in both territories on a compassionate-use basis.

Protherics also wants to fund improvements to the manufacturing processes of its ovine polyclonal antibodies. That would include increasing stocks of serum from its sheep in Australia, expansion of the purification facility in Wales and investment in qualifying a further filling and freeze-drying contractor in the U.S.

Andrew Heath, CEO, said, "By investing now, we aim to increase our returns from Voraxaze and to make further significant reductions in the manufacturing costs of our polyclonal antibody portfolio."

Protherics made its first profits in the financial year ended March 31, mainly due to U.S. sales of CroFab, a rattlesnake antivenom, and DigiFab, for treating overdoses of the heart drug digoxin.

It expects the investment in sales and marketing of Voraxaze to enable it to retain much of the product's value. That is in contrast to its existing marketed antibodies, from which it receives a 50 percent royalty rate. Once Voraxaze is approved, Protherics intends to conduct trials to expand the label.

The company's strategy is to use revenues from Voraxaze to fund development of its earlier-stage products. Those include NQ02, a prodrug activated by an enzyme expressed in some solid tumors, which is in Phase I; an angiotensin vaccine for treating hypertension, which has completed a Phase II trial and now is being reformulated with a new adjuvant; and CytoFab, a polyclonal antibody for sepsis, which has completed Phase II.

Protherics has hopes of securing a licensing deal for CytoFab, having agreed to a Phase III trial design and changes to the manufacturing process with the FDA that will reduce the size, timeline and cost of Phase III trials.