Are Biosimilar Drugs the Future of Cancer Treatment?
Some of the most exciting advancements in cancer treatment involve biologic therapies.
Made with living organisms, biologics prompt the immune system to kill cancer cells.
Biosimilars are similar versions of biologics already approved by the U.S. Food and Drug Administration (FDA).
The FDA approved the first biosimilar in 2015.
Now the agency has approved the first biosimilar to treat cancer.
The drug is called bevacizumab-awwb (Mvasi).
It’s a biosimilar to bevacizumab (Avastin), which gained approval in 2004.
Both drugs are approved for treatment of adults with certain colorectal, lung, brain, kidney, and cervical cancers.
Mvasi was developed by Amgen, Inc. The company hasn’t announced a launch date.
Similar but not interchangeable
The biosimilar Mvasi is similar to its reference drug Avastin.
But it’s not what the FDA classifies as interchangeable.
Julie Kennerly, PharmD, assistant director of pharmacy at The Ohio State University Wexner Medical Center, explains.
“Generic drugs are, essentially, copies of brand name drugs. You can automatically substitute the generic. Biosimilars are not an exact replica the way a generic is. They’re highly similar to the reference product. But they have some allowable differences due to the fact that they’re made from living organisms and the complexity of the manufacturing process,” Kennerly told Healthline.
“They don’t lend themselves to be reproduced exactly. Mvasi can be used for the same indications as Avastin. We can expect clinical outcomes to be the same. But the physician has to indicate one or the other. They can’t be switched or changed without a new prescription,” she continued.
She noted that biosimilars are allowed because of the Biologics Price Competition and Innovation Act of 2009. So, they’re fairly new.
“We’re just starting to see them come to market,” said Kennerly.
To be called interchangeable, the drug must meet the same standards as biosimilars. In addition, they must prove they can produce the same result as the reference product in any patient, even if they switch from one drug to the other.
More cancer biosimilars on the way
Kennerly believes more biosimilars for cancer treatment will be available in the near future.
She said that others in the pipeline include biosimilars for trastuzumab (Herceptin), pegfilgrastim (Neulasta), and rituximab (Rituxan).
Getting biosimilars into general use is more complicated than it is for generics.
How will doctors choose which drug to prescribe?
Much will depend on how medical insurers respond, according to Kennerly.
Kennerly suggested it might be particularly challenging for outpatient infusion centers to decide how much of each drug to stock.
But cancer centers are likely to have more success in deciding which ones to use.
The impact on healthcare costs
Biologics are expensive and a big driver of escalating healthcare costs.
In the United States, generic drugs saved the healthcare system $253 billion in 2016 alone.
It remains to be seen if biosimilars will have a similar impact.
Dr. Timothy Byun, a medical oncologist with St. Joseph Hospital’s Center for Cancer Prevention and Treatment, said it’s not clear how Mvasi will affect cost of treatment.
“Obviously on the surface, this should help to curb the rising cost of cancer treatment. But medical economics does not appear to follow the rules of true market economy,” he told Healthline.
“If you have a product that is similar, then that drug’s cost should be substantially less expensive. However, some health insurances have co-pay policy that may end up making generic drugs more expensive for patients. We will have to wait and see whether patients pay more out-of-pocket for Mvasi compared to Avastin,” Byun said.
Kennerly believes biosimilars will end up decreasing the cost of cancer care.
But estimating how much is a complicated task.
“Competition drives prices down. What is unknown is how far. This will largely be determined based on the CMS [Center for Medicare and Medicaid Services] ruling on how to approach reimbursement for biosimilars. What the CMS does, insurers usually follow suit,” said Kennerly.
“The current CMS policy requires all biosimilars related to the reference products be given a shared code. Reimbursement is based on the average sell price. The challenge is that it could end up stifling the biosimilar production market,” she continued.
“Many people have urged the CMS to reverse its current biosimilar reimbursement policy. The 2018 final regulations from CMS are expected in November,” said Kennerly.
What does it all mean for cancer patients?
Cancer patients won’t necessarily see any difference, said Kennerly.
“The whole idea behind biosimilars is that the FDA has vetted them and approved them as similar enough. I don’t think the patient will really see a difference, outside of potentially the pricing scheme that’s utilized,” she said.
With current biosimilars on the market, Kennerly said the main difference for the patient is what insurance covers.
“Pharmacy benefits are driven primarily by insurers. As the healthcare provider, you don’t necessarily have as much say, perhaps, as you would like,” she said.
Byun emphasized that biosimilars have the same efficacy and safety profiles as brand name biologic drugs.
“They [patients] should not be fearful when oncologists use biosimilars,” he said.