The trials were being carried out on those suffering from muscular dystrophy and Motor Neuron Disease (MND).

Doctors in charge of the trials have said they are disappointed with the results. Professor Madhuri Behari, head of AIIMS’ neurology department, said: “A lot still needs to be done on this subject. It is unfortunate these trials had to be abandoned. The patients underwent stem-cell therapy for over a year. They showed little progress initially but none after that.” Both trials were conducted by her department.

The advanced research has also failed to work on patients with cardio-vascular diseases or those who suffered strokes. Initial results had indicated the doctors were on the right track, but that was it.

The treatment of heart and stroke patients began in 2005 under the aegis of former AIIMS director Dr P Venugopal. The immediate results had excited experts, who thought the efficacy of stem-cell therapy might have been proved beyond doubt. But three years on, they have realised there is need for more extensive research before one can emphatically talk about the effects of this treatment.

Dr Sujata Mohanty, in-charge of the stem-cell facility at AIIMS, said: “Trials done on heart and stroke patients have not been completely evaluated. It won’t be correct to say that we have achieved the desired results.”

Dr P Venugopal, under whose guidance the stem-cell facility in the institute took shape, is not worried by the results. He said: “It is an established fact that stem cells are effective. We need to read the reasons behind the recent failures. This can happen if the follow-up is not according to laid down rules.”

Apart from the two trials, doctors are at present working on stem-cell research in strokes, cerebral palsy, injuries of the spinal cord and Parkinson’s Disease. Most trials are assisted by the Department of Science and Technology.

Though disheartened, doctors are hopeful. Dr Mohanty said: “We might not have got all the answers now. We don’t know which group benefitted more from the trials — those with chronic diseases or the ones diagnosed recently. The trial is still in its infancy.”