A drug that is the “gold standard” for treating cancer in children is in increasingly short supply after one of two manufacturers stopped making it, alarming parents and causing doctors to fear what will happen if the shortage drags on.
“It scares me obviously,” said Nicole Starace, 45, of Hauppauge, whose 6-year-old son Ryan has leukemia and uses the drug vincristine. “It’s something that is part of his treatment that’s keeping him on the right path to being cured.”
Dr. Lawrence Wolfe, a pediatric oncologist at Cohen Children’s Medical Center in New Hyde Park and a professor at the Zucker School of Medicine at Hofstra/Northwell, said Cohen has a stockpile of vincristine and “we’re pretty confident our current patient population should be OK.” But he said if there is an influx of new cancer patients to Cohen and the shortage lasts too long, there may not be enough of the drug to go around.
“This would be devastating to patients and families if we reach the point where we actually run out,” he said.
Vincristine is a key reason most children survive cancer, he said. It has been a linchpin in the treatment of childhood cancer for decades. In July, Teva Pharmaceutical Industries “made a business decision to discontinue the product,” the U.S. Food and Drug Administration said in a July 5 posting on its website.
The last remaining producer of the drug, Pfizer, said in a statement that, because of the Teva decision, the company is “expediting additional shipments of this critical product over the next few weeks to support three to four times our typical production output. Pfizer is committed to providing this important medicine to patients.” Pfizer said in an alert posted on the FDA website Wednesday that the company expected the shortage to last until December or January, depending on the dosage.
Teva spokeswoman Kelley Dougherty said in an email Tuesday afternoon that “availability of Teva product has not contributed to the shortage that is being experienced today.” When the company in 2017 conducted an analysis of the need for vincristine, Teva had only 15% of the market, she said.
Like Cohen, Stony Brook Children’s Hospital appears to have a large enough supply of vincristine to get through the shortage, said Dr. Laura Hogan, division chief for pediatric hematology and oncology at the hospital.
But if Pfizer isn’t able to produce enough vincristine, the hospital likely would be forced “unfortunately to ration it to those for whom we think that the doses were more important than others,” which include children being treated in the weeks and months after diagnosis, when vincristine typically is used most frequently and aggressively, rather than when the disease is in remission.
“We’d have to prioritize those for who we thought losing it would have the greatest impact on survival,” Hogan said. “That doesn’t work out very well if your child happens to be the one who is near the end of therapy and who doesn’t get it.”
The typical starting dose for vincristine in pediatric cancer patients is once a week, according to Pfizer. It is administered intravenously. That dosage usually is reduced as the disease goes into remission, Wolfe said.
Ryan was diagnosed with acute lymphocytic leukemia in February 2017, Starace said. His dosage was reduced to once a month and, two weeks ago, to once every three months, she said. He is scheduled to continue treatment until May 2020.
Ryan is “doing awesome,” Starace said. But she doesn’t want to take any chances.
“Everything is mapped out and every dosage is prescribed based on his protocol and his treatment plan,” she said. “He shouldn’t miss any dose.”
Vincristine is used in combination with other chemotherapy drugs, Wolfe said. It stops the growth of cancer cells and makes it easier for other chemotherapy medications to kill the cells, he said.
If there is not enough vincristine to treat all those who need it, doctors may turn to drugs that have a higher level of toxicity and that have more severe side effects.
“We are concerned that without it, it will be more difficult to achieve a cure,” he said.
Vincristine is used in adults to treat lymphoma but is primarily used to treat children with leukemia, sarcoma and other types of cancer, Wolfe said.
That, Wolfe said, may be why there is a production problem. Cancer is far more common in adults than in children — fewer than 1% of cancer diagnoses each year are in children, according to the American Cancer Society — and drugs typically are more lucrative if more people need them, he said. There have in recent years been shortages of other drugs that treat childhood cancer, he said — but the vincristine shortage is different because most kids with cancer take it, he said.
“To be honest, if more adults needed vincristine we probably would not be in a vincristine shortage,” Wolfe said.
And vincristine is relatively inexpensive, which likely means lower profit margins, he said.
“There just isn’t much interest from a fiscal perspective to support it and keep it going, even though if you look at childhood cancer, it’s one of our major curative chemotherapy drugs,” he said.