The average sales prices for Pfizer’s trastuzumab and rituximab biosimilars are falling far below those of their competitors’—by as much as 93%.
In the newly released fourth-quarter report on biosimilar trends from Samsung Bioepis, one item stood out among the sea of now-familiar trend lines: A new drop in average sales prices (ASPs) for two oncology products, both from Pfizer.
The notable developments represent some large changes on a percentage basis. For Pfizer’s trastuzumab biosimilar, Trazimera, the ASP has dropped from $325 for a 420-mg dose in the third quarter, to $255 for the same dose in the fourth quarter. This is nearly 75% below the ASPs for the three closest competitors (Ogiviri at $1,021, Hercessi at $1,052, and Ontruzant at $1,159). This is also 93% below the ASP of the reference product Herceptin.
However, the difference is even greater for Pfizer’s Ruxience. In the third quarter of this year, its ASP was $531 for a 500-mg dose. This has dropped precipitously, to only $289 for the same dose. The next closest competitor is Riabni, at $782. (In the Samsung report, the price was listed at only $18. This may be the result of erroneously removing the product’s 8% ASP markup [of $5.44 per 10 mg] from CMS’s listed average manufacturer’s price. Many thanks to IPD Analytics for their help in the calculation). Ruxience’s current ASP is now 92.5% below the ASP price of the reference product Rituxan.
However, the demand for these two biosimilars does not seem to follow the pricing. Consider that the ASP data are reported for the fourth quarter of 2026, and the marketshare data is from the second quarter, so there is a 6-month gap or lag. Still, both of these Pfizer products were the least expensive in their respective drug categories for the third quarter as well.
In the trastuzumab class, Trazimera has a 21% marketshare, behind Kanjinti (at 35%) and Ogviri (at 23%). Kanjinti’s ASP is the highest for a biosimilar trastuzumab, at $2,464, with Ogviri at around $1,100, about fivefold greater than Trazimera. For rituximab, Ruxience is the number 2 rituximab biosimilar, at 34% marketshare, behind Truxima (at 37%). Truxima’s ASP was $1,527, or fivefold more than Ruxience.
This sounds like another opportunity for Medicare plans to employ reference pricing to help drive buy-and-bill providers towards the lowest-cost agent.
In Other Biosimilar News
Xbrane Biopharma secured FDA approval for its ranibizumab biosimilar Lucamzi (ranibizumab-blrz) on October 26. This marks the fourth ranibizumab biosimilar approval, and the first US biosimilar approval for the Swedish manufacturer Xbrane. In a press release, the company announced a planned 2027 “together with its partners,” which have yet to be disclosed.
“FDA approval of Lucamzi is a landmark event for Xbrane, representing a key opportunity to reach many more patients and to realize a return on our development investments,” commented Martin Åmark, CEO of Xbrane.
