British researchers said on Tuesday that an Alzheimer’s drug designed to attack abnormal tangles in the brain appeared to slow progression of the disease in a phase II trial.

The announcement, made during the International Conference on Alzheimer’s Disease in Chicago, said “the drug could be over twice as effective as any treatment currently available” Clive Ballard, head of research for the Alzheimer’s Society said.

There are currently five drugs approved to treat Alzheimer’s, which causes a progressive loss of memory and mental faculty, but they only mask symptoms for 6 to 12 months at most. Therefore, pharmaceutical companies have long tried to develop a drug, which could do more than that in helping millions of Alzheimer’s patients worldwide. There is even more pressure, as the number of patients with Alzheimer’s disease is going to quadruple by 2050 reaching approximately 106 million cases.

The new drug called Rember was developed by private biotechnology company TauRX and produced a significant improvement in thinking and memory, two cognitive abilities affected by the Alzheimer’s disease.

The drugs may work by dissolving tangles of a protein (tau protein) that collects in the brain cells of Alzheimer’s patients, researchers conducted by Claude Wischik of Aberdeen University’s Institute of Medical Sciences who has spend two decades tracing the role of tau protein tangles in Alzheimer’s disease.

“We have demonstrated for the first time that it may possible to arrest the progression of this disease by targeting the tangles which are highly correlated with the disease. This is the most significant development in the treatment of the tangles since Alois Alzheimer discovered them in 1907,” Wischik said in a statement.

The drug, a purified form of a substance commonly known as methylene blue (also used for urinary tract infections and carbon monoxide poisoning for decades), was tested on 321 patients with mild to moderate Alzheimer’s disease at 17 centers in the UK and Singapore. The patients were divided in two groups receiving rember or a placebo.

After six months of treatment, the people on placebo lost an average of 7 percent of their brain function whereas those on rember did not decline at all. The decline continued after a year on those taking placebos. The same situation was registered at 19 months from the beginning of the trial. Brain scans showed rember was active in brain areas most affected by tau tangles, Wischik said.

Although the findings are encouraging, many researchers present at the conference feared to conclude on the efficiency of rember. Given the fact that it was a phase II trail, predictions are hard to make.

“It’s a phase 2 trial. Predicting anything from a phase 2 trial is dangerous. All I can say is it is encouraging enough to move on to a phase 3 trial,” Dr. Sam Gandy, of Mount Sinai School of Medicine in New York, who serves on an advisory council of the Alzheimer's Association said.

Wischik said if the drug show promise in a phase III trial, it could be available for general used by 2012 or 2013.