By Deidre McPhillips, CNN

CNN — 

As the US faces a near-record number of drug shortages, cancer treatments are among the hardest hit.

There is an active shortage of about two dozen chemotherapy drugs, the fifth most of any drug category, according to data from the end of March from the University of Utah Drug Information Service.

“The fact that we have this many chemo drugs in shortage is really concerning,” said Michael Ganio, senior director of pharmacy practice and quality at the American Society of Health-System Pharmacists.

Unlike some other drugs that also rank among the top five categories for shortages, such as antimicrobials, there aren’t often alternatives for chemotherapy drugs, he said. And the shortages are affecting treatment for a broad range of cancers.

“One of the key predictors of how well a patient will respond to treatment is getting a full dose on the right schedule,” Ganio said. “So when we can’t give the drug because we just can’t get the drug, that’s heartbreaking.”

Overall, data from the University of Utah shows that there were more than 300 drugs with an active shortage in the US at the end of March, including nearly 50 new shortages that accumulated in the first three months of the year.

The last time active drug shortages – including both newly reported and ongoing – were this high was in 2014, the data shows.

“Shortages are still happening, and they’re not resolving, or they’re not resolving as quickly as new shortages are starting,” Ganio said.

On Thursday, the US House of Representatives’ Energy and Commerce Subcommittee on Oversight and Investigations held a hearing exploring the root causes of these shortages.

Increased demand is part of it. But experts say that some high-profile shortages – such as amoxicillin during the most recent respiratory virus season and Adderall for ADHD – are the exception.

“They don’t really tell the story of drug shortages,” Ganio said.

Instead, the hearing was more heavily focused on manufacturing issues and the broader structure of the drug market in the US.

The US Food and Drug Administration, in particular, was criticized for falling behind on inspections, especially of international facilities that represent more than half of manufacturers that supply the US.

A report from the Government Accountability Office, a federal watchdog agency, in January 2022 noted “longstanding challenges” facing the FDA’s Foreign Inspection Program and called for more formal steps to improve it.

Effective inspections of both domestic and foreign manufacturing facilities are “absolutely essential for ensuring the quality and the safety of the medicines that US citizens consume,” said Anthony Sardella, chair of the API Innovation Center, a nonprofit focused on building the supply of US-made pharmaceuticals.

“They’re also extremely important in ensuring the stability of the market,” said Sardella, who was a witness at the hearing.

But in a hearing Thursday of the Energy and Commerce Subcommittee on Health, FDA Commissioner Dr. Robert Califf said that the economic issues underlying drug shortages are “not in the purview of the FDA.”

The FDA is “plugging holes in the dike,” he said, but it’s difficult to motivate change when it’s not profitable for drug companies.

“These drug shortages are becoming more prevalent due to a warped marketplace,” said Rep. Kathy Castor, D-Florida, ranking member on the subcommittee.

“The current haphazard approach of addressing crisis episode-by-episode is not working to give American families the certainty and the quality of care they need and deserve.”

Hundreds of impending shortages loom, and Califf called on drug companies to alert the FDA to them.

“Each company doesn’t know what the other company’s doing because they’re competing,” he said. “When there’s a shortage in one company, we need to be able to coordinate across these people.”

Outside of the FDA, there is a small team of officials at the White House focused on bolstering drug supply chains and quality, a senior administration official confirmed to CNN. The team was first reported by Bloomberg News.

The team, the senior official said, has been “meeting for some time” and is made up of “several” White House offices, including the Domestic Policy Council and the National Economic Council.

“The Biden-Harris Administration remains focused on strengthening the resilience of critical supply chains, including for medical products like pharmaceuticals,” the official said, pointing to five executive orders issued by President Joe Biden since taking office aimed at “[catalyzing] whole-of-government action toward these objectives.”

Blame aside, patients remain at the heart of the issue.

“There is severe patient impact happening every day,” said Laura Bray, founder of Angels for Change, an advocacy group focused on ending drug shortages. “We also can’t forget the emotional trauma that you’re putting on a family in medical crisis.”

She experienced it firsthand in 2019 when her 9-year-old daughter, Abby, couldn’t get the drug needed to treat her leukemia because there was a shortage.

Abby is doing well now, but 9 out of 10 oncologists say that drug shortages have led to patient harm, including death, said Bray, who was a witness at the Oversight hearing Thursday.

“Patients deserve access to these medicines. The physicians and nurses and care team who are trying to solve these crises and save them deserve easy and equal access to these medicines.”

CNN’s Jacqueline Howard and Betsy Klein contributed to this report.