By in Biography & Personal Stories —

From Diagnosis to Discovery: The Physician Who Cured Himself

Diagnosed with a fatal rare disease, medical student David Fajgenbaum became his own lead researcher. Facing imminent death after treatments failed, he analyzed his own blood to identify an existing drug that would save his life and is now pioneering a new model for patient-centric research.

From Diagnosis to Discovery: The Physician Who Cured Himself

The Patient in Lab Coat One

For most medical students, the most terrifying ordeal is an exam. For David Fajgenbaum, it was his own body. In 2010, the third-year student at the University of Pennsylvania was suddenly struck by a maelstrom of symptoms: extreme fatigue, night sweats, and widespread organ failure. Doctors delivered a grim diagnosis: idiopathic multicentric Castleman disease (iMCD), a rare and deadly immune disorder where the body’s own defenses turn into an uncontrolled mob, attacking vital organs in what's known as a 'cytokine storm.' The prognosis was bleak, and a cure was non-existent.

A Citadel Under Siege

Over the next few years, Fajgenbaum’s life became a cycle of near-fatal relapses and brutal treatments. He endured rounds of chemotherapy and experimental drugs, including powerful IL-6 blockers, but the remissions were tragically brief. Five times he stared death in the face; on one occasion, a priest was called to administer his last rites. But between these terrifying episodes, a new resolve hardened. He was not just a patient; he was a physician in training, armed with a unique perspective. He realized that the researchers studying his disease were working in isolated silos, and no one was connecting the dots for patients like him who had exhausted all known options.

From Data to Deliverance

Taking his fate into his own hands, Fajgenbaum began a radical new project: he turned himself into a case study. He established the Castleman Disease Collaborative Network (CDCN) from his hospital bed, uniting a global community of physicians and researchers. He then embarked on a systematic hunt for his own cure. With the tenacity of a detective, he collected his own blood and tissue samples, meticulously tracking 11 different cytokines and other biomarkers during both remission and relapse. He was searching for a signal in the noise of his own biology.

The breakthrough came when he noticed a pattern. His data pointed to an overactive signaling pathway known as PI3K/AKT/mTOR in his T-cells, a crucial part of the immune system. This pathway was acting like a stuck accelerator pedal, fueling the cytokine storm. The solution, he hypothesized, might not be a novel drug, but a repurposed one. He identified sirolimus, an FDA-approved immunosuppressant typically used to prevent organ rejection in kidney transplant patients, as a potent inhibitor of the mTOR pathway.

I’m in my longest remission ever thanks to a drug that I found in the lab that had never been used for my disease before, and now we’re working to see how many other patients it can help. I feel like I’m living in overtime, and I’m dedicating every waking moment to advancing this new way of doing research for my disease and other diseases like it.

The Blueprint for a Cure

With his own life on the line, he began taking sirolimus. The results were astounding. The relapses stopped. Today, Dr. Fajgenbaum has been in remission for over a decade. But his work was far from over. His personal victory became a blueprint for a new approach to medical research—one that is collaborative, patient-centric, and relentlessly focused on repurposing existing therapies. Through the CDCN, he now applies this model to accelerate the discovery of treatments for Castleman disease and other rare disorders, offering hope to countless patients who, like him, were once told there was none.

Sources