PatientsLikeMe is a social networking site that enables patients to share information around disease conditions. It was started in 2004 by concerned family members of an individual with ALS (Lou Gehrig’s disease). Users can register for free and interact around eleven conditions: ALS/Motor Neuron Disease, Anxiety, Bipolar, Depression, HIV/AIDS, Multiple Sclerosis, OCD, Parkinson’s disease, PLS, PMA and PTSD. For a site focused on limited number of disease conditions, they get some serious traction:

PatientsLikeMe enables affected individuals to find others with similar condition, share experiences, and learn what works and what doesn’t. Users can also track their progress and keep up with relevant research. The knowledge of first hand information about a disease experience, treatment effectiveness or side effect is very powerful for managing these complex multi-system diseases.

Needless to say, the rich data generated by such a focused and engaged community is invaluable for research. So no surprise that one of the revenue models behind PatientsLikeMe is the sale of anonymized data from and permission-based access to their user community.

June’10 Update: Case in point about the usefulness of sites like PatientsLikeMe. Last month Lancet Neurology published a study showing that the generic drug lithium did nothing to slow the course of ALS. PatientsLikeMe community had reached the same conclusion 18 months earlier, much more quickly and at much less cost. In 2008, after a small Italian study suggested that lithium could delay the progression of ALS, about 10 percent of PatientsLikeMe’s ALS users began taking the drug, not wanting to wait for a larger trial to confirm the results. Inspired by a member in Brazil who wanted to know if lithium was truly helping, the company rolled out a number of tools to allow patients to track their progress. You can see their fantastic report page here.