Eli Lilly and Co. announced Monday that its experimental drug is effective in slowing down memory loss in Alzheimer's disease by 34 percent.

The drug solanezumab was effective in slowing down cognitive decline in people who had mild to moderate levels of Alzheimer's but not as much as was expected. The pooled result of two studies conducted on the drug showed that people who took the drug over an 18-month period had a 34 percent lower cognitive decline than people who took a placebo.

Detailed results of the EXPEDITION studies were announced on Monday at the American Neurological Association conference in Boston. The drug trial results were analyzed by the Alzheimer's Disease Cooperative Study (ADCS), an academic research consortium. The trials consisted of two studies, each with about a 1,000 participants, aged 55-94 years, from 16 countries.

"This is a complex disease that touches millions of people worldwide. Alzheimer's disease causes significant burden on patients, caregivers and our society. While the path forward has not been determined, we believe these data in patients with mild disease may provide a step toward a potential treatment option," said David Ricks, senior vice president and president, Lilly Bio-Medicines in a press release.

The new drug targets the amyloid plaque that clogs up the brain in people who have Alzheimer's disease, The Associated Press reports.

News of the drug showing somewhat positive results drove up the shares of Eli Lilly by as much as 5.6 percent (at $50.78) on Monday. Reuters Health said that investors were encouraged that the drug trial results would be considered by the U.S Food and Drug Administration.

"Today's data supports the view that solanezumab may be active in early Alzheimer's patients but that further clinical work will likely be needed prior to FDA approval of the product," Chris Schott, J.P. Morgan analyst told Reuters.

Further clinical trials will be required before the drug can be accepted as a good treatment option for the disease.

Dr. Sam Gandy said that the benefits of the latest drug are less than earlier drugs that had promised to slow down the disease "I hate to get too enthusiastic ... there's a flicker of a signal" ( of benefit). Gandy is head of Alzheimer's research at the Mount Sinai School of Medicine in New York, The Associated Press reported.

This news is promising for solanezumab after the drug had failed two earlier tests. As reported by Medical Daily, the drug did not meet its end points but had promising results in a late stage trial and was waiting for analysis by the ADCS.

Recently, Pfizer Inc and Johnson & Johnson had scrapped tests for a similar drug - bapineuzumab - aimed at slowing down Alzheimer's after its disappointing results in drug trials.