Outcomes Model Is Starting With Gene Therapy for Sickle Cell Disease

State healthcare plans struggling to pay for multimillion-dollar gene therapies got a lifeline this summer when the federal government launched a novel plan to negotiate fees and rebates to cover the costs for the medicines. But will the move sway patients who haven’t flocked to the potential cures?

The Cell and Gene Therapy Access Model, launched by the CMS in July, allows CMS to negotiate outcomes-based contracts with drugmakers on behalf of states. So far, 33, along with Washington, D.C., and Puerto Rico, have joined the program. As part of the agreement, drugmakers will be required to provide rebates to states if the therapies fail to deliver their expected
clinical benefits.

The program is initially focusing on treatments for sickle cell disease, for which there are two approved gene therapies, Vertex Pharmaceuticals Inc.’s Casgevy (exagamglogene autotemcel) and Bluebird Bio Inc.’s Lyfgenia (lovotibeglogene autotemcel), although CMS is exploring expanding the program into different conditions and therapies in the future. The participating states collectively represent about 84% of Medicaid enrollees with sickle cell disease.

“This model is a game changer,” said CMS Administrator Mehmet Oz, M.D., in a July 15 news release. “CMS is giving states the tools to deliver lifesaving therapies to patients in need, while holding manufacturers accountable for outcomes and protecting taxpayer dollars.”

Shared risk

By centralizing negotiations, CMS aims to lower prices and simplify contracting for states. Medicaid agencies that opt in are required to adopt standardized access criteria and agree to the terms CMS establishes with manufacturers.

Approximately 100,000 people in the U.S. have sickle cell disease, a genetic blood disorder that disproportionately affects Black Americans. Left untreated, the condition can cause severe pain, organ damage and premature death. Casgevy and Lyfgenia work by editing or replacing patients’ own cells to stop the blockages in blood vessels that define sickle cell disease. Unlike daily medications that manage symptoms, these one-time treatments aim to eliminate the underlying cause of the disease entirely.

But the complexities of gene therapy create obstacles. Patients must understand concepts like cell modification, gene editing and the lengthy treatment process that can involve chemotherapy-like conditioning. Religious and cultural concerns about altering genetic material add another layer of consideration for some.

Sluggish sales

The high costs of these gene therapies are considered justified when compared with the lifelong costs these patients incur with frequent bleeds, hospital stays and other treatments. But they can still cause budget shocks to state Medicaid programs, according to a November 2024 white paper from the Institute for Clinical and Economic Review (ICER) and Tufts Medical Center’s NEWDIGS consortium.

“As the healthcare payment ecosystem prepares for the growing number of gene therapies entering the market, three key interconnected challenges must be addressed: determining a fair price, managing clinical uncertainty and managing short-term budget impacts,” according to the paper.

The CMS program, which was described in a request for applications in 2024, addresses some of these problems with sickle cell disease and should be expanded to accommodate other conditions. ICER and NEWDIGS wrote, “Currently, the program is focused only on expanding access to gene therapies for sickle cell disease but might serve as a model that could be expanded to include all gene therapies or be designed to allow coverage eligibility for patients with any form of primary health insurance.”

Sales of the sickle cell gene therapies have been sluggish. During its first-quarter earnings call in May 2025, Vertex reported that eight patients had completed their treatment during the three-month time period, with another 90 starting the cell collection process; Bluebird Bio reported product revenue of $12.4 million for Lyfgenia in the first quarter of 2025, or about four doses (priced at $3.1 million per dose).

Outreach tools

Advocates are working to create better tools to educate and inform patients regarding the treatments. Two organizations, Through The Pain Inc. and UCSF Sickle Cell Center of Excellence, are creating an education program that brings together patients, families, doctors and researchers to pinpoint exactly where understanding breaks down. The team plans to develop materials that address specific gaps using perspectives that resonate with diverse communities.

While the new model addresses pricing and reimbursement, patient advocacy organizations have cautioned that equitable access will require more than financial reform.

“For a long time, the only disease-modifying therapy for sickle cell disease was hydroxyurea, which doesn’t work for many sickle cell patients and leaves the community with limited options for care,” said Edward Donnell Ivy, M.D., M.P.H., chief medical officer of the Sickle Cell Disease Association of America, in a statement. “The new gene therapies that were approved by the FDA in 2023 will allow individuals the opportunity for transformative therapy with a potential cure.”

Donnell said that the cost of these drugs has contributed to the limited access, but the new program may help alleviate that aspect. “It is important for CMS and other stakeholders to get involved in ensuring access to this therapy, particularly since it has been demonstrated that a large portion of the sickle cell population relies on Medicaid for access to care,” he said.

Managing logistics

Patients undergoing gene therapy for sickle cell disease typically require an extended inpatient hospital stay, preparatory chemotherapy and multiple follow-up visits to a specialized treatment center. These challenges can create barriers to access even after coverage is secured.

To help meet those challenges, the CMS program also provides technical assistance and nearly $10 million per state in funding to support patient services and to cover the costs of travel, behavioral health care and fertility preservation, which is a critical need since chemotherapy used in gene therapy can cause infertility.

Still, Medicaid officials acknowledge that successful implementation will require new levels of coordination between state agencies, managed care organizations and out-of-state providers. Tracking long-term outcomes has been difficult because states collect different types of data in a wide variety of formats. CMS plans to use existing sickle cell registries and provider reporting systems, but some stakeholders have raised concerns about the administrative burden and the time lag between treatment and measurable results.

“This agreement is a major win for American patients and for Medicaid,” said HHS Secretary Robert F. Kennedy Jr. in the same CMS news release. “Thanks to the leadership of Dr. Oz, CMS is making this model a reality. I look forward to seeing states lead the charge to improve health outcomes at lower costs for the American people.”

Looking ahead

CMS has indicated it is exploring future expansions to include other high-cost therapies for rare conditions, including hemophilia and certain genetic pediatric disorders.

“This is CMS delivering innovation with purpose,” said Abe Sutton, director of the CMS Innovation Center and deputy CMS administrator. “By negotiating outcomes-based agreements with drugmakers, we are helping states lead on access and affordability simultaneously.”