Evidence to Support Zarxio Use Presented at AMCP

Two posters presented at the Academy of Managed Care Pharmacy bolstered the case for moving away from the use of the originator filgrastim product Neupogen®.

In a study from Magellan Rx Management, Scottsdale, AZ, the researchers grouped both Zarxio® and Granixzarxio® together as alternatives to the originator filgrastim in the granulocyte-colony-stimulating factor (G-CSF) category as supportive oncological care. They studied the effect of a step edit, requiring the use of either Zarxio or Granix first, and its effect on utilization trends and cost savings among 2.7 million covered lives.

The step edit was implemented in October 2016 and the results for the fourth quarter of 2016 were compared with utilization and cost data from the first three quarters of that year. In terms of utilization, the marketshare of Neupogen dropped from 18% in early 2016 to only 2% by the third quarter of 2017. As expected, the drop in utilization occurred just after the step edit was introduced a year ago. The combined marketshare of Granix and Zarxio jumped from 9% to 21% over that time, but the dominant player in the G-CSF space, Neulasta® (pegfilgrastim), maintained utilization, rising from 73% to 77%. Over the one-year period since the step edit was introduced, the authors calculated a cost savings of $662,278; the cost savings in the quarter after the policy change was $106,980, or approximately 8% of the total spent for the G-CSF category.

The authors noted that the cost savings were calculated using wholesale acquisition cost (WAC) not average sales price (ASP), and manufacturer discounts or rebates were not considered in the estimates.

The second poster, sponsored by Sandoz, was a retrospective claims analysis of the incidence of febrile neutropenia in patients receiving chemotherapy who were treated with Zarxio or Neupogen. This study covered 13 months of claims (from Optum) from 162 patients taking Zarxio compared with 3,297 receiving Neupogen. The groups did not differ significantly in terms of demographics, insurance, or tumor type.

The researchers found that the incidence of neutropenia (in addition to fever and/or infection) was nonsignificantly greater in those receiving the biosimilar compared with the reference product (2.3% vs. 1.7%, respectively).

The FDA Rejects Mylan/Biocon’s Pegfilgrastim; Market Still Awaits a Biosimilar for Neulasta

In the latest blow to those seeking an alternative to Amgen’s Neulasta®, the Food and Drug Administration (FDA) sent a complete response letter to Biocon, citing manufacturing plant deficiencies, in its rejection of their biosimilar pegfilgrastim application.

Announced on October 10, this is the second biosimilar from Indian manufacturer Biocon that has been detoured by manufacturing plant problems. Its Bangalore plant, where the partners’ biosimilar trastuzumab was to be manufactured, was also cited earlier this year.

In August, Biocon and its marketing partner Mylan withdrew its European Medicines Agency applications for pegfilgrastim and trastuzumab after receiving negative reports on its manufacturing facility.

This is the second FDA biosimilar rejection relating to plant deficiencies. In June, the agency issued a complete response letter to Pfizer, resulting from a legacy Hospira plant in Kansas.

In the press release announcing the latest setback to its pegfilgrastim biosimilar, Biocon said that the complete response letter relates to “facility requalification activities post recent plant modifications. The CRL did not raise any questions on biosimilarity, pharmacokinetic/pharmacodynamic data, clinical data or immunogenicity.”

Biocon also stated that “We do not expect this [complete response letter] to impact the commercial launch timing of biosimilar pegfilgrastim in the US.” Although Mylan and Biocon had not publicly announced an intended launch date once it received approval, Amgen’s principal patents for Neulasta have expired. One might have expected a relatively quick launch of its biosimilar, considering the 180-day postlaunch exclusivity period no longer exists and the possibility of other players in the market, including Coherus, Pfizer, and Apotex (all of whom received complete response letters).

Mylan and Biocon Withdraw Two EMA Biosimilar Applications

The biosimilar pegfilgrastim marketplace may have taken another hit today, as Biocon announced that it was pulling its applications for both pegfilgrastim and trastuzumab from consideration by the European Medicines Agency (EMA).

The action came after Biocon was notified of the need for re-inspection of its manufacturing site by the European authorities. According to Reuters, Biocon said in a stock filing, “The European regulatory authorities had informed us of the need for a re-inspection of our drug product facility for these products,” Biocon said, without specifying when the regulator would carry out the inspection.

Herceptin“We are on track to complete our corrective action and preventive actions by the end of this quarter, and it is our intent to seek re-inspection and re-submission thereafter.”

In another report, a Biocon spokesperson stated that “Whilst our drug substance facilities for trastuzumab and pegfilgrastim were approved, the European regulatory authorities had informed us of the need for a re-inspection of our drug product facility for these products. The request for withdrawal of the dossiers and re-submission is part of the EMA procedural requirements linked to this re-inspection and will be considered by the EMA’s Committee for Medicinal Products for Human Use (CHMP),” said the company spokesperson.

This action could potentially create considerable problems for the partners Mylan and Biocon. They have the opportunity to be first-to-market in the US with regard to both biosimilar products. Their biosimilar trastuzumab application received a unanimous recommendation to approve from the Food and Drug Administration (FDA) Oncology Drug Advisory Committtee in July, and a final decision is imminent (expected before September 3). The partners’ biosimilar pegfilgrastim application is expected by October 9th. Although the FDA usually rules according to its Advisory Committee recommendations, manufacturing plant problems has resulted in at least one surprising rejection, for Pfizer’s Retacrit®. Pegfilgrastim applications have not yet made it through the FDA approval process, after three previous attempts.   

Information is not readily available as to whether the Biocon plant that is subject to re-inspection would potentially be supplying products to the US. If so, the FDA may decide to review the situation, and possibly delay their decision or issue complete response letters on the two products.

Pegfilgrastim: 0 for 3 on Biosimilars at FDA

On June 12, Coherus Biosciences received word of the Food and Drug Administration’s (FDA’s) rejection of its biosimilar pegfilgrastim. Manufacturers have now taken 3 swings and misses, striking out in their quest for a biosimilar version of another blockbuster product.

In 2016, Sandoz whiffed on its version, after having the nonpegylated version approved in 2015 (Zarxio®). Although details of the FDA’s complete response letter were not released, Sandoz decided to withdraw its application to the European Medicines Agency as well. In December 2014, Apotex was the first to submit its pegfilgrastim application to the FDA, but it was similarly rejected.

The remaining biosimilar version of Neulasta® awaiting its turn at bat in the US is from Mylan/Biocon. Submitted in February of this year, the FDA decision is due October 9, 2017. Pfizer is working on its own version of pegfilgrastim (HSP-130), which is in phase 2 study. Apotex’s Apobiologix unit is still seeking approval of its biosimilar, according to its website. In Europe, 2 pegfilgrastim applications are currently awaiting decisions, but none have been approved to date.Image result for pegfilgrastim (neulasta)

On the bright side, the FDA’s complete response letter to Coherus did not indicate that the game is over. Apparently, the agency asked for a re-analysis of specific data and requested further information regarding manufacturing its biosimilar agent. The drug maker indicated its willingness to work with FDA to resolve these concerns.

There seems to be something about the pegylated version of filgrastim that makes it more difficult to obtain an approval during the first plate appearance. It may well be that Mylan’s application hits it out of the park in October. However, the batting average of drug makers pitching their other biosimilars is far better—Pfizer’s second try at approving epoetin seems to have been a hit (with a 14-1 margin by the FDA Advisory Committee).

With $4.5 billion in US sales of Neulasta last year, there will be no shortage of hitters willing to come to the plate.