The International Society for Stem Cell Research (ISSCR), the leading professional organization of stem cell scientists, representing more than 3,600 members in the United States and over 60 other countries, opposes the REGROW Act, which would allow certain cell and tissue-based therapeutics to be marketed without first providing rigorous evidence of safety and efficacy. If passed, this legislation could negatively impact the development of stem cell therapies, the integrity of the emerging regenerative medicine market, and the health and safety of people using stem cell products approved under this Act.
Stem cell-based products, like drugs, are currently tested for toxicity in Phase I trials, preliminary evidence of safety and therapeutic effectiveness in Phase II, and for definitive evidence of safety and effectiveness in large, controlled Phase III trials. This three-stage approach to testing ensures that physicians and patients have information on the risks and benefits of these products before they use them.
The initial version of the REGROW Act, S.2689, sought to eliminate Phase III clinical trials, which are needed to determine whether a new stem cell product is safe and effective. This would have allowed companies to sell new treatments with only preliminary evidence of safety and a vaguely defined “reasonable expectation of effectiveness” based on small-scale clinical studies.
A more recent version of the Act creates an expedited development pathway within the FDA solely for regenerative medicine products. Unlike other FDA accelerated review programs, any regenerative medicine product would be eligible for expedited approval regardless of whether it addresses an unmet medical need or a life-threatening illness. If REGROW is enacted, this authority would require that such products undergo a single Phase II trial and no Phase III trials.
History shows that a great many experimental therapies that look promising in Phase I and II clinical trials subsequently fail, proving to be either unsafe or ineffective upon more rigorous testing in Phase III. In recent years, as many as 40% of drug and biotechnology products that enter Phase III fail due to safety concerns or lack of efficacy. If the lower standards in the REGROW Act are enacted, many new products that enter the market would likely be ineffective and possibly unsafe.
Phase III clinical trials are also necessary because they generate information that is used to guide life and death treatment decisions made by patients and their physicians. If either version of the REGROW Act becomes law, patients and their doctors would not have access to robust data on the safety or effectiveness of new treatments. New treatments would be made available to the public without being compared, side-by-side, in Phase III clinical trials with the best therapies currently available.
Under both versions of the REGROW Act, healthcare costs would be expected to accelerate without comparable advances in medical outcomes. If new products can be sold to patients before their effectiveness is rigorously demonstrated, the government, private healthcare systems, and insurers may be compelled to reimburse the costs of new treatments without knowing whether they work.
In addition, the provision of unproven treatments is an international issue and any change in U.S. cell therapy approval policy is liable to have strong, negative repercussions around the world.
The ISSCR recognizes that the financing of large clinical trials is a major challenge for the development of stem cell therapies and that improvements can be made in the current system for approving new therapies in the United States. However, a one-size-fits-all approach, such as the REGROW Act, is not the solution. Instead, Congress should give the FDA the flexibility and authority to act as quickly as scientifically and medically prudent to review and approve safe and effective treatments while guarding against the sale of unproven therapies. Fast track authority should be granted only when it is scientifically and medically justified. The FDA already has mechanisms in place to grant fast track authority when it is warranted.