Adam M. Brufsky, MD, PhD, discusses the impact of biosimilars in the field of oncology and outlined other strategies and steps that can be taken to mitigate cost when treating patients with breast cancer.
Adam M. Brufsky, MD, PhD
For those who might question the equivalence of biosimilars to their reference products, it is important to remember the strict guidelines in place to ensure similarity before they reach the United States market, explained Adam M. Brufsky, MD, PhD.
In December 2018, the FDA approved a second trastuzumab (Herceptin) biosimilar, CT-P6 (Herzuma; trastuzumab-pkrb). CT-P6 is indicated for patients with adjuvant HER2-overexpressing node-positive or -negative breast cancer to be used as part of a treatment regimen comprised of doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel, or as part of a regimen with docetaxel and carboplatin.
The biosimilar is also indicated as a frontline treatment for patients with HER2-positive metastatic breast cancer to be used in combination with paclitaxel, or as a single agent to treat patients with HER2-positive breast cancer who received 1 or more chemotherapy regimens for metastatic disease.
The CT-P6 approval comes 1 year after the first trastuzumab biosimilar, MYL-1401O (Ogivri; trastuzumab-dkst), was granted FDA approval for the treatment of patients with HER2-positive breast cancer or metastatic gastric adenocarcinoma.
While these trastuzumab biosimilars will certainly impact the HER2-positive space when they become commercially available in the United States, Brufsky said there are other biosimilars that are also making headway in the oncology space. For example, Zarxio (filgrastim-sndz), which is the G-CSF analog of filgrastim (Neupogen), and pegfilgrastim-cbqv (CHS-1701; Udenyca), a pegfilgrastim (Neulasta) biosimilar, are already being used in practice.
As for the cost effectiveness of biosimilars, Brufsky, a professor of medicine and co-director of the Comprehensive Breast Cancer Center at the University of Pittsburgh, predicted that these products could potentially drive down the price of antineoplastics by up to 20%.
In an interview with OncLive, Brufsky shared insight on the impact of biosimilars in the field of oncology and outlined other strategies and steps that can be taken to mitigate cost when treating patients with breast cancer.Brufsky: While the trastuzumab biosimilars have been approved, they have not been marketed yet, which means that no one has actually started using them [in practice yet]. There are some biosimilars that will impact the field more quickly. For example, we have already been using the biosimilar G-CSF and there is now a pegylated biosimilar G-CSF that has been recently approved as well. Several trastuzumab biosimilars will probably receive approval in the next year or so.
When they reach market, it is important to remember that they must be similar [to trastuzumab] in terms of efficacy. If the biosimilars are superior or inferior, they [would not have been] approved. The only real difference [between biosimilars and reference products] is the cost, and what is going to happen is that the cost of care will be reduced.
This [cost reduction] is a big deal for society in general—not just in the oncology space. Everyone from our president to Congress wants to reduce drug costs. Biosimilars will go a long way, at least in the breast oncology space, particularly with the [introduction of the] trastuzumab biosimilars [into practice]. They will help reduce the cost of care by at least 15% to 20%, if not more. These products have to be similar to the reference products; that is the whole idea. They must be similar in terms of biology, and there are several glycosylation assays that need to be done on the molecule to show it is almost exactly the same. The toxicity profile has to be same. Biosimilars cannot be inferior or superior; if they are, that defeats the purpose of their development and they will not be approved. There is a very specific process that the FDA has devised to determine if these drugs are the same. Therefore, to any skeptic who says that they these products are not the same: They have to be; that's number 1.
Additionally, according to the initial data from Europe, at least in the area of breast cancer, cost has gone down by about 30%. Biosimilars have taken off a lot quicker in Europe. That is how I would answer the skeptics. I would say that the cost has to go down because it creates competition. When there is not a single-source drug anymore, the cost has to naturally go down. Now, it is incumbent on the purveyors of the biosimilars to ensure that this is the case. That is the reason we use them. To me, if there is not at least a 15% reduction in cost, it will not be worth it. It is an interesting question, and some of these efforts are already underway. I am involved with developing the Via Oncology Pathways for breast cancer and when we look at these pathways, it is interesting that many these drugs are generic. We use generic chemotherapy, anastrozole, tamoxifen, etc. The vast majority of what we are doing is generic, but the thing is, when we introduce that drug, we have to be sure that it works.
First, we should have a biomarker predictive of response. Second, we should look for potential de-escalation strategies like the one we are seeing used with trastuzumab. If trastuzumab can be given for 6 months instead of 12 months, that would save the patient and the payer a lot of money. Another question is, “Should we use pertuzumab (Perjeta) in the adjuvant setting and will patients benefit from this drug?” Before biosimilars come out, these are the things we are looking at. Patient and payer education are going to be crucial in terms of having them understand that biosimilars are completely the same [as the reference products]. They will be upset if they think they are paying for something that is not equivalent in all the areas we discussed. Physicians need to be less nervous about giving biosimilars, and they need to understand when it is the right time to use a biosimilar. Right now, the pharmaceutical companies that seem interested in promoting biosimilars are doing a decent job of starting that process.