Cornelius F. Waller, MD: Filgrastim and pegfilgrastim are the first 2 biosimilar drugs in supportive care that got approval in the United States. Filgrastim has been approved in Europe for quite a while, and pegfilgrastim is expected to follow soon. I think that both are major advancements, as were the reference products because of the lower risk of neutropenia associated with using these drugs. They already have had a huge impact. In Germany, for example, the market share of the biosimilar filgrastim is in the range of 75% to 80% over the average with regard to prescriptions. So the biosimilar market has sped up quite a bit over the past few years.
In addition to these 2 biosimilars, filgrastim derivatives and monoclonal antibodies, such as rituximab, came to the market. The market share for the rituximab biosimilar, after the first 7 months, rose to around 10% of the prescribed rituximab product overall. Because of the cost savings, this will increase even more in other countries. I consider this similar.
Trastuzumab biosimilars and bevacizumab biosimilars that are in development could be available within the next year or so. We will see how this will impact the treatment of solid tumors differently from the filgrastim derivatives for supportive care. With these antibodies, we have direct cancer treatment. The results of the clinical trials are quite promising because biosimilarity could be shown for several of these compounds.
In Western countries, I don’t consider it necessary to change. Because of the healthcare systems, the availability for the reference product, as in the United States, is comparable, I think. However, in third-world countries or poorer countries, this will definitely change the treatment plan. In certain areas, such as in Eastern Europe, drugs such as trastuzumab have not been available for HER2/neu-positive patients, which is something we can hardly imagine. Because these drugs are going to become available, I think it will change the treatment for these patients.
I believe that the availability of biosimilars will change the treatment plans for many patients in poorer countries or third-world countries where biologics are not available, mostly because they have been too expensive for the healthcare system. I hope that having the chance to use biosimilar compounds such as filgrastim, pegfilgrastim, and monoclonal antibodies will provide availability in these countries. The outcomes of treatment will improve, and the likelihood of dying from cancer, in certain situations, can be decreased with the use of these drugs.
The likelihood of patients’ having neutropenia has been decreased with the use of filgrastim and pegfilgrastim. But if you don’t have it available and get intensive chemotherapy—because certain diseases can only be treated intensively—the likelihood of higher morbidity and mortality is pretty clear and can be lowered with these therapies. For example, for HER2/neu-positive breast cancer, the clear message is that the use of HER2/neu-directed antibodies leads to a better prognosis for these patients. If you can treat them with a drug that was not possible before, it will lead to better outcomes.