AstraZeneca looks to Iressa successor after setback
pharmafile | December 16, 2004 | News story | Research and Development |
AstraZeneca says it is optimistic about two of its most advanced cancer pipeline drugs, which it hopes will offset a serious setback to another because of unexpected side-effects.
ZD6126, a potential treatment for a range of solid tumours, demonstrated toxic side-effects in phase II trials and has now been sent back to the laboratory for further testing.
The setback is a further headache for the Anglo-Swedish company which has built its reputation on groundbreaking cancer drugs.
The company had hoped the drug would be a successor to its current rising star in breast cancer treatment, Arimidex, which in turn built on the reputation tamoxifen (branded as Nolvadex), currently the gold standard in breast cancer treatment.
Meanwhile, results are expected shortly from ZD6474, a drug designed to block the formation of blood vessels to supply tumours, thus holding back their growth. The drug is similar to the firm's lung cancer drug, Iressa, although it has the extra mechanism of action in blood vessels.
Dr George Blackledge, medical director of AstraZeneca's cancer research division, said: "It has two actions, one is Iressa-like, the second is against the blood vessels. Unless we prove it is different to Iressa we probably don't have a competitive drug."
But Dr Blackledge said there was some ''exciting" data on another drug, AZN2171, which is in phase I development and also works to inhibit the formation of blood vessels.
He said: "This is one that may move very quickly, assuming that the very encouraging data holds up."
Two further candidates with potential, AZN6244 and AZN3409 are expected to start phase II trials in 2005.
The UK's second largest pharmaceutical company has been hit by drug setbacks throughout 2004, most notably the FDA rejection of Exanta because of safety and efficacy doubts.
The first-in-class oral direct thrombin inhibitor may have to undergo further clinical trials to convince the FDA, or otherwise face prescribing restrictions which would limit its commercial potential.
