“Amy is the health policy leader and convener we need to drive creative solutions,” Mahaniah said in a statement Thursday. “Her deep understanding of the people we serve – particularly access and affordability issues – and her strong relationships across the health care system in our state will serve Massachusetts residents well.”

Rosenthal will oversee the state’s Medicaid, public health, and mental health departments.

“This is a really vital time. There are a lot of implications for Massachusetts with all the federal cuts coming down the pike,” Rosenthal said in a brief interview Thursday. “If I’m going to be in any state, I’m glad to be here in Massachusetts.”

This summer, Congress approved new restrictions on Medicaid, including eligibility checks every six months and a new requirement that most able-bodied adults between 19 and 64 years old without dependent children document they are either working, in school, or volunteering at least 80 hours a month. Congressional Republicans described the changes as ways to reduce fraud and abuse in the system, but in practice are likely to make it more difficult for thousands in Massachusetts to access coverage they’re entitled to receive.

State officials estimate that at least 300,000 more people in Massachusetts could become uninsured over the next decade, in large part due to the new Medicaid requirements. The state also may lose about $3.5 billion in funding, officials have said.

HHS is gearing up for a community engagement and outreach initiative to keep people eligible for Medicaid enrolled in the program. People experiencing homelessness, mental illness, or who rarely use their health insurance are considered particularly vulnerable to losing their coverage, because it’s hard for them to keep track of the new documentation they need to stay enrolled

During Rosenthal’s tenure with Health Care for All, which began in 2017, the state contracted with the nonprofit to conduct community outreach to improve uptake of COVID vaccines and to ensure people eligible for Medicaid didn’t lose coverage during an effort last year to cull from the rolls people who no longer qualified for the program.

The COVID vaccination program improved immunization rates in nine communities hit hard by the virus, according to the nonprofit.

During the pandemic, federal law barred states from conducting eligibility checks on people enrolled in Medicaid. From 2023 to 2024, Massachusetts ran a redetermination effort to review membership and identify people who didn’t qualify for the program. Health experts feared the process, which required statewide re-enrollment in Medicaid, would lead people who should receive public insurance coverage to get left behind. In response, Health Care for All ran another major door knocking and information campaign that allowed 42,000 people who might otherwise have lost their insurance to keep it, the organization reported.

During her time with Health Care for All, Rosenthal also successfully advocated for Medicaid reforms, including improved prescription drug access, adult dental coverage, and extended coverage during pregnancy.

“Amy Rosenthal has been a voice for the voiceless and a support for those falling through the cracks – including countless patients and families struggling to find the services they need,“ said Steve Walsh, chief executive of the Massachusetts Health and Hospital Association, in a statement Thursday

Health Care for All promoted Ashley Blackburn, senior director of policy and government relations, to deputy executive director, and she will act as interim director while the organization’s board conducts a search to permanently fill that position.

Before joining the nonprofit, Rosenthal was a leader at Community Catalyst, a Boston organization that works to expand health equity and played a role in passing and implementing the Affordable Care Act.

Rosenthal has a bachelor’s degree from Northwestern University, a master’s degree in public health from Harvard, and a master’s degree in public affairs from Indiana University.

Jason Laughlin can be reached at jason.laughlin@globe.com. Follow him @jasmlaughlin.