Belén Garijo has been Chair of the Executive Board and Chief Executive Officer of Merck since May 2021, leading the company through major strategic transformation across its Life Science, Healthcare, and Electronics business sectors. She joined Merck in 2011 as Chief Operating Officer of the Biopharma business, became President and CEO of the Healthcare business sector in 2015, and was promoted to group CEO with responsibility for global communications, strategy, science and technology, compliance, and M&A.
Under Garijo’s leadership, Merck strengthened its global presence in oncology and immunology by realigning the Healthcare portfolio that includes the scientific and clinical origins of one of the world’s most widely used immune checkpoint inhibitors, a therapy that reshaped modern cancer treatment. She steered the company through the COVID-19 pandemic and geopolitical volatility while driving profitable growth, including targeted portfolio moves such as the acquisition of SpringWorks Therapeutics and the divestiture of Surface Solutions. Garijo has been recognized on international lists of powerful business leaders and received honors for her impact on diversity and transatlantic industry relations.
The 100 CEOs featured here reflect the diversity and complexity of modern oncology leadership. In 2025, some lead the world’s largest cancer institutions; others guide specialized societies or emerging innovators. What unites them is responsibility: for millions of patients, for the integrity of science, and for the future direction of cancer care globally.
This list is not a celebration of power, but a recognition of stewardship, accountability, and impact – and of the leaders whose choices continue to shape the fight against cancer. For the many deserving individuals not mentioned in this list, we will continue to acknowledge, honor and elevate your voices in our daily publications from across the world.
See the full list of The 100 Most Influential CEOs in Oncology in 2025, and stay tuned for other special category nominations.
