Pfizer scraps cancer clinical trial

Novel treatment does not demonstrate superiority over chemotherapy

Pfizer has discontinued a Phase III clinical trial that was studying a potential treatment for advanced melanoma. The trial for tremelimumab was stopped as the drug seemed to be no better than standard chemotherapy. Initially, it was believed that the treatment could stimulate patients' immune systems to attack their tumours, even in melanoma patients.

"Although this outcome is disappointing, Pfizer remains committed to investigating new treatment options for patients with melanoma, a high-risk area of research with a significant unmet medical need. We continue to focus on additional studies involving tremelimumab alone, and combined with other therapies that are currently ongoing in patients with several types of cancer," says Charles Baum, Vice President and Oncology Therapeutic Area Head at Pfizer Global Research and Development. "We will continue to assess the study data to understand the clinical benefit seen in some patients who received tremelimumab."

The company has already communicated with worldwide regulatory authorities regarding the discontinuation of the trial. Investigators will now work with their patients to determine if they are benefiting from treatment and whether they should continue. Full data from the study are being analysed and more details are expected to be available at the upcoming American Society for Clinical Oncology Annual Meeting next month.

"We have a robust pipeline and we remain committed to the discovery and development of novel cancer treatments that hold promise for patients with cancer," says Baum. Pfizer is still developing several classes of agents including CD40 agonists, toll-like receptor agonists and vaccines.

http://www.pfizer.com/

Ants: the key to better drugs?

GERRY ELLIS/GETTY IMAGES

Researchers in the US claim that studies involving ants could lead to new antibiotics against gram-negative bacteria, such asEscherichia coliand salmonella. Two proteins have been discovered that guide one of two groups of pathogenic bacteria that make an ant's hardy outer shell, and create the barrier that protects the bacteria from the rest of the world.

The researchers, based at Princeton University (NJ, USA), discovered the proteins through an extended process of elimination by examining microbes inside carpenter ants. The bacteria have lived there for millions of years, been passed on with generations, and have lost many of the traits necessary for survival in the outer world. This makes their genome far simpler than that ofE. coli, which is so complex that scientists have been unable to assign a function to many of the thousands of proteins contained within the bacteria. The genome of the bacteria found inside the ants contains only 583 proteins, and nearly all of these are found inE. coli.Natividad Ruiz, lead author of the paper describing the work, says: "The long-term goal is to find inhibitors of these proteins. Small molecule inhibitors could become antibiotics that subvert the outer membrane."

http://www.princeton.edu/

Smoking genes identified

A company has found an answer to the long-asked question as to why some people are more likely to become addicted to cigarettes and, consequently, are at greater risk of developing lung cancer. According to scientists from deCode Genetics (Iceland), there is a clear link between a single-letter variant in the sequence of the human genome (SNP) and susceptibility to nicotine dependence. Each risk variant present confers an approximate 30% increase in the risk of lung cancer and a 20% increase in the risk of peripheral arterial diseases (PAD). It is believed that half of people of European descent carry at least one copy of the variant. The company now intends to apply its findings to develop a DNA-based test that can be used to increase the effectiveness of smoking cessation efforts, and predict the risk of lung cancer and PAD.

"These findings provide an example of the power of human genetics for shedding light on the most complex health challenges. Not only have we made a convincing link between a single SNP and a behavioural disorder, but also demonstrated how this risk factor translates into risk of lung cancer and PAD," says Kari Stefansson, CEO of deCode. "This is an important advance that we will use in our diagnostics programmes to develop means to enable individuals and their doctors to better understand and reduce the risk of smoking to their health."

http://www.decode.com/