Friday, December 19, 2014

New study reveals how COX-2 inhibitors can increase risk of heart attack in arthritis patients

In continuation of my update COX-2

A class of drug for treating arthritis - all but shelved over fears about side effects - may be given a new lease of life, following the discovery of a possible way to identify which patients should avoid using it.

The new study, led by Imperial College London and published in the journal Circulation, sheds new light on the 10-year-old question of how COX-2 inhibitors - a type of non-steroidal anti-inflammatory drug (NSAID) - can increase the risk of heart attack in some people.

NSAIDs - which include very familiar drugs such as ibuprofen, diclofenac and aspirin - are widely-used treatments for debilitating inflammatory conditions such as arthritis as well as being used for general pain relief worldwide. NSAIDs are also being investigated for their potential to prevent cancer. COX-2 inhibitors, which include Vioxx and Celebrex, were developed in the 1990s to avoid the risk of stomach ulcers caused by some NSAIDs, but after they were linked to an increased risk of heart attacks, they rapidly fell out of favour and some brands, including Vioxx, were withdrawn.

The new study, in mice and human volunteers, was led by Professor Jane Mitchell and Dr James Leiper. Professor Mitchell, from the National Heart and Lung Institute at Imperial, said:

Thursday, December 18, 2014

Drugs delay disease progression for women with hormone-receptor-positive metastatic breast cancer

A new combination of cancer drugs delayed disease progression for patients with hormone-receptor-positive metastatic breast cancer, according to a multi-center phase II trial. The findings of the randomized study (S6-03) were presented at the 2014 San Antonio Breast Cancer Symposium, held Dec. 6-9, by Kerin Adelson, M.D., assistant professor of medical oncology at Yale Cancer Center and chief quality officer at Smilow Cancer Hospital at Yale-New Haven.

The trial enrolled 118 post-menopausal women with metastatic hormone-receptor-positive breast cancer whose cancer continued to progress after being treated with an aromatase inhibitor. The study, based on work done by Doris Germain of Mt. Sinai Hospital, found that the combination of the drugs bortezomib and fulvestrant — versus fulvestrant alone — doubled the rate of survival at 12 months and reduced the chance of cancer progression overall.

Bortezomib, used most commonly in treating multiple myeloma, is a proteasome inhibitor that prevents cancer cells from clearing toxic material. Fulvestrant causes clumping of the estrogen-receptor protein. When bortezomib blocks the ability of the cell to clear these protein clumps, they grow larger and become toxic to the cancer cells. This, in turn, amplifies the effectiveness of fulvestrant, a drug commonly used in this subset of patients.

Friday, December 12, 2014

Spinach chlorophyll activates polymer production line



Inspired by nature, scientists in Australia have united light and chlorophyll to generate a range of polymers that have biomedical applications.



During photosynthesis, chlorophyll is activated by visible light, and an electron is promoted from its ground state to an excited state. In plants, this excited electron goes on to react with carbon dioxide and water, via photoinduced electron transfer (PET). However, in the system devised by Cyrille Boyer and colleagues at the University of New South Wales, the excited electron is donated to a monomer, generating a radical, which then goes on to further react and generate polymers through a process known as living radical polymerisation.


One of the challenges in polymer synthesis is achieving control over the length and structure of the polymers generated. Boyer’s team has addressed this using a form of living polymerisation called reversible addition fragmentation chain transfer, or RAFT, polymerisation, which incorporates an agent, normally a thiocarbonlythio compound, as a mediating species. The RAFT agent is capable of accepting and donating radicals, thus ‘sharing’ the radicals around evenly between the species present, ensuring each polymer chain has the opportunity to grow at an equal rate. This leads to a narrow range of polymer lengths and molecular weights (a low polydispersity index), and a high degree of control over the reaction. Various architectures, including star-shaped, comb-shaped and ring-shaped polymers can be synthesised in this way.

Monday, December 8, 2014

Experimental Cholesterol-Lowering Drug Effective, Study Reports

An experimental antibody drug, alirocumab could prove effective at lowering LDL ("bad") cholesterol levels for patients who have side effects with cholesterol-lowering statin medications.
That's the conclusion of a clinical trial presented Monday at the American Heart Association annual meeting in Chicago.

Monday, December 1, 2014

Researchers discover why advanced melanoma patients respond to pembrolizumab drug

Work supported by the Stand Up To Cancer (SU2C) - Cancer Research Institute (CRI) - Immunology Translational Research Dream Team, launched in 2012 to focus on how the patient's own immune system can be harnessed to treat some cancers have pioneered an approach to predict why advanced melanoma patients respond to a new life-saving melanoma drug. This new drug, pembrolizumab (Keytruda), was recently approved by the FDA. These findings are reported in Nature online November 26, 2014, ahead of print in the journal.

Over a two-year study, researchers including Dr. Antoni Ribas of UCLA Jonsson Cancer Center and co-leader of the CRI-SU2C Immunology Dream studied 46 patients with advanced melanoma treated with pembrolizumab. These patients had tumor biopsies before and during treatment. The researchers analyzed those biopsies and classified them according to whether the patient responded or not to pembrolizumab. The study then used the biopsy findings to predict the likelihood whether patients would likely to respond to this treatment

Novartis to present first IL-17A Phase III data for AIN457 (secukinumab) in Psoriatic Arthritis and Ankylosing Spondylitis