Xenova Group plc has signed an agreement with a London cancerresearch organization to develop a drug that in preclinical studiesindicated it may inhibit cancer cell replication and overcome drugresistance associated with chemotherapy.London-based Xenova has agreed to pay about $2.5 million to theCancer Research Campaign (CRC) for the rights to manage later-stageclinical trials of the drug, called XR5000, and market the product.Payments, some of which will include Xenova stock, will be based oncertain milestone achievements and CRC will receive royalties on anysales.The CRC's technology group has Phase I clinical trials under way inBritain and additional Phase I trials are planned for New Zealand.Initially Xenova and CRC will target treatment of small cell lungcancer and skin cancer.Xenova's Trevor Twose, director of corporate planning anddevelopment, told BioWorld his company will be responsible for PhaseII and Phase III trials in the U.K. and U.S. He said Phase II trials in theU.K. are expected to begin in the second half of 1995, but he would notspeculate on when studies will begin in the U.S."All the information on XR5000 shows that it is a pretty importantcancer drug if its promise holds out in clinical trials," Twose said.XR5000, he added, is the first anti-cancer drug that has shown anability in laboratory tests to inhibit both topoisomerases I and II, whichare enzymes involved in cancer cell proliferation. Current cancer drugstarget one or the other, but not both.Another significant aspect of the preclinical data, Twose said, is thatXR5000 showed it may be able to overcome resistance to anticancercompounds, such as doxorubicin and etoposide. The resistance isassociated with p-glycoproteins and mutated topoisomerases II. P-glycoproteins are overexpressed in cancer cells and pump the drugsoutside the cells before the therapeutic compounds can work.Researchers at the University of Auckland in New Zealand inventedXR5000 and will participate with CRC and Xenova in the developmentof the drug.Xenova's stock (NASDAQ:XNVAS) closed Wednesday at $8.50 ashare, up 50 cents. _ Charles Craig081294

(c) 1997 American Health Consultants. All rights reserved.