“Preventative medicine” is a great idea, except for the small caveat that the concept has saved few lives at a substantial cost. For example, according to researchers at the Harvard School of Public Health and Tufts–New England Medical Center, screening all 65-year-olds for diabetes (as opposed to screening only 65-year-olds with hypertension for diabetes) costs hundreds of thousands of dollars for each year of life saved. But what if a one-time shot early in life could prevent diseases such as diabetes altogether, saving countless lives and health care dollars? Fortunately, a new line of treatment—gene replacement therapy—offers the game-changing benefits to patients that doctors could only dream of a decade ago. And, this new technology could save taxpayers billions of dollars.

Strimvelis, a stem-cell gene therapy used to treat a rare, devastating immunodeficiency disease known as ADA-SCID, can treat patients in a single shot. This shot eliminates a lifelong need for expensive, painful therapies. Zolgensma, which awaits approval by American, European, and Japanese regulators, can cure spinal muscular atrophy (SMA) in infants. These wonder drugs will soon be joined by dozens of others, as gene therapies targeting multiple rare, chronic diseases start the regulatory application process.

But with costs north of $500,000 for many treatments, not all regulatory agencies—and insurance bodies—are on board to approve gene therapies. The Food and Drug Administration (FDA) has lagged behind its European Commission counterpart in approving these game-changing medications, and there’s little indication of how government insurers such as Medicare will deal with gene therapy. Despite the high upfront costs and miraculous-sounding claims, the evidence is clear: these therapies save lives and millions of dollars over the long-term.

In a 2017 study published in The Journal of Clinical Investigation, researchers found a remarkable result—9 out of the 10 children with ADA-SCID treated via gene therapy at the Mattel Children’s Hospital in Los Angeles recovered from the disease and needed no further treatment. This was just the latest piece of evidence in a growing body of promising clinical work, which had led the European Commission to approve the therapy in 2016. But many balk at its price tag of around $700,000, which very few could afford up-front.

For many ADA-SCID sufferers that can’t get a bone-marrow transplant, few options are available. The most common option is a multi-year treatment known as enzyme replacement therapy, which requires patients to go through an intravenous injection. The treatment costs an astounding $300,000 per year, and it takes months for the treatment to have an effect on the immune system. In the best-case scenario, patients use the therapy for at least five years and keep their immune systems free of infection and disease. Gene therapy costs half that, promising patients less cost, far fewer hospital visits, and less lag time before immune protection takes effect. Similarly, Zolgensma is slated to cost $2 million, a bargain compared to the $10 million cost of caring for SMA patients over a decade. For taxpayer-funded healthcare programs, that is an amazing cost saving.

Current gene therapies are just the start of a multi-decade effort to revolutionize health care and liberate billions from pain and suffering.

According to the American Medical Association, around 4,000 diseases—ranging from cystic fibrosis to cardiovascular disease—are linked to genetic disorders. Doctors have developed strategies to control these diseases and minimize their consequences, prescribing mucus-thinning drugs for cystic fibrosis and placing stents into the arteries of patients with heart disease. But these treatments are costly and will need to be repeated in the absence of therapies that address the roots of devastating, chronic conditions.

New gene therapies are currently being developed for these more-common conditions, but it will be difficult to bring these products to market without a receptive regulatory and payment system. Funding these therapies for elderly patients through the Medicare system may cost the federal government more upfront, even though it will surely save taxpayers over the long-run. To bridge that gap between present and future, the Spanish government has already begun experimenting with something called “amortization” in health-care payments, essentially repayment plans averaged over a long time-frame.

Existing gene therapies show that victims of terrible diseases can be quickly cured through one shot, instead of 100 shots, 20 medications, and 10 high-risk surgeries. That benefits patients and payers and will benefit an increasing share of the population—if regulators and insurers respond appropriately. Medical innovation that can save lives and taxpayers money is on the not-so-distant horizon, but only if government regulators recognize the breakthroughs and allow these new medical procedures to flourish, not flounder.