José Baselga, MD, PhD, was internationally renowned as a major force in the development of molecularly targeted therapies and in making precision cancer medicine a reality for patients, died March 21, 2021, at the age of 61.

Baselga was born in Barcelona, Spain, on July 3, 1959. He earned his medical and doctoral degrees from Universitat Autònoma de Barcelona. Early in his career, he helped found the Vall d’Hebron Institute of Oncology at Vall d’Hebron University Hospital in Barcelona. Baselga served as chairman of medical oncology and helped develop the institute into one of the major translational research and cancer treatment centers in Europe.

Baselga’s research focused on developing therapeutics that target genetic mutations in tumors and on understanding the mechanisms of drug resistance. Throughout his career, he led preclinical and early-stage clinical studies of targeted therapies for breast cancer. He conducted the initial clinical trial that demonstrated that patients with advanced HER2-positive breast cancer benefited from treatment with the anti-HER2 monoclonal antibody trastuzumab (Herceptin). The U.S. Food and Drug Administration approved trastuzumab in 1998, and since then it has been used to treat more than 2.3 million patients.

Baselga also helped develop everolimus (Afinitor), lapatinib (Tykerb), and pertuzumab (Perjeta), which are breast cancer treatments that have been used alone or in combination with other therapeutics for the benefit of countless cancer patients.

Although his early work focused on breast cancer, his expertise helped guide research into numerous other cancer types. In recent years, Baselga’s work contributed to the development of trastuzumab deruxtecan and datopotamab deruxtecan, antibody-drug conjugates that have shown promise in patients with advanced non-small cell lung cancer.

From 2010 to 2013, Baselga was the chief of the Division of Hematology/Oncology and associate director at the Massachusetts General Hospital Cancer Center, also serving as professor of medicine at Harvard Medical School. He then joined Memorial Sloan Kettering Cancer Center as physician-in-chief and chief medical officer, serving additionally as professor of medicine at Weill Cornell Medical College. He is credited with establishing Memorial Sloan Kettering as a leader in early-phase clinical trials and in diagnostic genetic sequencing. In January 2019, he joined AstraZeneca as executive vice president for R&D oncology, forging collaborations with industry partners and championing the use of real-world evidence in clinical trials. He led a team aiming to accelerate progress in antibody-drug conjugates, cell therapy, epigenetics, and new cancer treatments. Baselga understood the power of basic science in the clinic, and his visionary work transformed treatment by bringing precision cancer medicine to the frontlines of standard of care.