The bad news is that Eli Lilly’s experimental Alzheimer’s treatment, solanezumab, failed to meet its primary endpoints in two late-stage clinical trials in patients with mild to moderate levels of the disease. The good news is that investigators saw positive signs in some analyses of the studies.

According to Lilly, after combining the results from all 2,050 participants in both trials, it found statistically significant signs that the drug slowed memory loss in some patients, many with mild cases.

“We’re encouraged by the signals we see here,” says David Ricks, president of Lilly Bio-Medicines. He said the solanezumab findings validated the company’s heavy investment in Alzheimer’s treatments. Lilly plans to discuss the findings with regulators before determining how to proceed with the drug.

Generally, combining the data from the two trials isn’t considered conclusive but is used to generate hypotheses that require further study and validation.

Importantly, the results from the pooled solanezumab data are the first from any late-stage Alzheimer’s studies to suggest a benefit from an anti-beta amyloid compound.

Full data from the studies, based on an independent analysis by an academic national research consortium called the Alzheimer’s Disease Cooperative Study, will be presented in October at scientific conferences in Boston and Monte Carlo, the company said.

As the Wall Street Journal reports, “Much will depend on how regulators interpret the data. Usually the U.S. Food and Drug Administration makes decisions based on how experimental therapies perform in meeting the primary goals of pivotal trials.” The Journal continues, “In the case of solanezumab, the FDA will have to weigh the potentially limited cognitive benefits against the lack of effective treatments, experts said. The agency could ask Lilly to do additional studies exploring further whether solanezumab does indeed slow down Alzheimer’s progression in certain patients.”

That’s true. But an even more important issue is understanding—and rewarding—incremental innovation. “Limited cognitive benefits” is in the eyes of the beholder, but the impact is anything but limited when it comes to our nation’s healthcare wallet.

As the prevalence impact of Alzheimer’s grows, so does the cost to the nation.

One in eight people age 65 and older, or 13 percent, has Alzheimer’s disease. Nearly half of people age 85 and older, or 45 percent, battle the disease. If Alzheimer’s disease were a tradable stock, the demographics of the Baby Boom generation would make it a “must buy.”

The direct and indirect costs of Alzheimer’s and other dementias amount to more than $148 billion annually, which is more than the annual sales of any retailer in the world excluding Wal-Mart.

Is there value in slowing the progression of Alzheimer’s disease? Certainly.

According to a study in Health Affairs, monthly savings of $2,029 in formal services are possible if Alzheimer’s disease progression can be slowed. Annual institutional cost savings of $9,132 also are achievable if alternative residential settings are used.

Sometimes the biggest success stories rest on the foundations of failure. The solanezumab trials may have missed their primary endpoints, but they have succeeded in advancing our knowledge of Alzheimer’s disease and provided a possible new and innovative option for patients (and family members) of this draconian disease.

Solanezumab will not be the magic bullet that eradicates Alzheimer’s disease from our lexicon of suffering, but it may yet be an important addition to our pharmacological armamentarium.

As FDA and then CMS decide on the value of solanezumab, it’s important to remember that innovation is slow. As any medical scientist will tell you, there are few “Eureka!” moments in health research. Progress comes step-by-step, one incremental innovation at a time.

As Harvard University health economist (and Obama healthcare advisor) David Cutler has noted, “Virtually every study of medical innovation suggests that changes in the nature of medical care over time are clearly worth the cost.”

The battle for the heart and soul of 21st century health care is the battle over innovation. And nothing short of victory is acceptable. To borrow an over-used adjective from the world of global climate change, we must protect “sustainable” innovation.

Peter J. Pitts is President of the Center for Medicine in the Public Interest and a former FDA Associate Commissioner