(NewsNation) — A Missouri couple is fighting to save their newborn twins after the family’s insurance said it won’t cover a potentially life-saving treatment.

The two boys were diagnosed with a rare genetic disease called “spinal muscular atrophy” just days after they were born, the family said in a Facebook post.

“Their life expectancy is one to two years without treatment,” the twins’ mother, Amanda Reed, told KCTV5. “It’s just been a nightmare, an absolute nightmare.”

The disease causes muscles to waste away, and without treatment, individuals can have trouble breathing and swallowing.

It’s a nightmare made worse by a recent change to the family’s insurance coverage, which Reed has through her work, Mosaic Life Care.

Each boy needs a one-time gene therapy treatment called Zolgensma, but the couple said their insurance stopped covering the therapy exactly one day after the boys were born.

Known as the world’s most expensive drug, Zolgensma will cost the family between $1 million and $2.5 million out-of-pocket per child, according to a GoFundMe set up to help the twins.

Infants who receive the one-time infusion before their symptoms begin often go on to live normal lives, Reed told the local news outlet. That means the family is in a race against time to get the boys the help they need.

Mosaic CEO Mike Poore pointed the blame at pharmaceutical companies and said they have made it impossible for employers to “bear the financial burden of these exorbitant drug prices” in a statement to KCTV5.

Poore said Mosaic’s Health Care Trustees made the “gut-wrenching decision” not to cover expensive gene therapy back in January because it could “cripple the financial viability” of the health system, adding that they’re trying to find financial resources to help “in this case.”