The Centers for Medicare & Medicaid Services is expanding its competitive bidding program for durable medical equipment to 91 new cities, for an estimated savings of $28 billion over 10 years, the agency announced last week.

The first phase of the bidding program, which started Jan. 1 in nine major metropolitan areas, has already saved the government $130 million in its first six months, according to CMS officials. Under the program, healthcare providers seeking DME supplies can purchase them only from approved companies submitting the lowest bid to the agency. These supplies include wheelchairs, oxygen supplies and hospital beds.

The program’s expansion will allow providers to bid on items such as negative pressure wound therapy pumps and related supplies, which are commonly used in nursing homes to treat pressure sores.

Earlier this year, long-term care experts said the program is based more on math than good policy.

But CMS officials say they are confident in the program’s benefits. “The success we’ve had in the first phase tells us that we can achieve these savings with no disruption for patients’ access and no negative effect on patients’ health,” said Jonathan Blum, deputy CMS administrator and director of the Center for Medicare.