Health Center Community Transformation Hub Act This bill permits the Health Resources and Services Administration (HRSA) to award supplemental funds to certain health centers that care for medically underserved populations for addressing primary social determinants of health (i.e., nonmedical factors that influence health outcomes, such as transportation, food security, and economic security). To receive the supplemental funding, health centers must be recipients of other HRSA grants that support health center operations and activities. Health centers must use the supplemental funds to implement a community-based network of organizations capable of addressing the social determinants of health. Additionally, HRSA and the Centers for Medicare & Medicaid Services must issue guidance on sustaining these networks after the supplemental funding terminates.