- Welcome back. Let's get right to our GMA cover story and the Nationwide generic cancer drug shortage frustrating doctors and putting patients at risk. [MUSIC PLAYING] This morning, medical experts are sounding the alarm on the nationwide generic cancer drug shortage, adding to the hardship on doctors and their patients. - The light at the end of the tunnel was there, and then to be thrown this curveball, just very shocking. - 39-year-old, Ryan Dwars, says he had just four rounds of chemotherapy left in his fight against pancreatic cancer when he received devastating news, the potentially life-saving drug he needed was in short supply. - There was priority just based on the need as far as rationing out goes. And so in my situation, I was not high enough in the area of need. - Dwars is one of the thousands of cancer patients across the country whose lives could be at risk due to a low stock of two popular generic chemo drugs, CISplatin and CARBOplatin. The Iowa father says he was taking CISplatin to shrink to cancerous spots on his liver, but the nationwide shortage forced his doctors to come up with a plan B last April. - What's also disheartening is the CISplatin was working with my cancer and it was very showing very positive results. - According to the FDA, there's currently a shortage of more than 130 drugs caused by factors like changes in demand, manufacturing problems, and supply chain issues. The American Cancer Society says cancer drugs are in the top five drug classes affected by shortages, and have limited treatment alternatives. - The application of chemotherapy is a science way more than it is an art, and it's a regimen. So it's like imagining that you're trying to make a cake, a very high stakes cake, and that you're missing a few eggs, you're missing a little flower, and thinking that the same thing is going to come out. It doesn't happen in cooking, and it certainly doesn't happen in cancer. - The Association for Accessible Medicine is telling ABC News in a statement, "It stands ready to work with the FDA and the administration to ensure that drug shortages are prevented and/or resolved as soon as possible to ensure patients benefit from safe, effective, and more affordable generic and biosimilar medicines." As for Dwars, he says he was able to work with a nonprofit organization to source the CISplatin he needed to receive his final treatments. - It was very stressful. We're already going through difficult times with our health situations. And so to have to have that added stress, it was just very difficult. - And the FDA telling ABC News it is working closely with numerous manufacturers and others in its supply chain to understand, mitigate, and prevent or reduce the impact of intermittent or reduced availability of certain products, and that it expects availability to increase in the near future. But, I mean, could you imagine? It's terrifying enough to fight cancer, and then have to deal with this on top of it is just so frustrating and difficult. - And scary too for patients.