Celltrion’s Rituximab Biosimilar Earns Positive Review

The information package released by reviewers for the Food and Drug Administration (FDA) indicates that a positive recommendation for Celltrion’s rituximab biosimilar is likely at the Advisory Committee meeting on October 10.

The members of the Oncologic Drugs Advisory Committee will review the data and hear public comments before voting to recommend that the FDA ultimately approve or reject CT-P10 for the treatment of non-Hodgkin lymphoma. Celltrion did not perform clinical trials for rituximab’s autoimmune indications. However, if the FDA approves CT-P10, it may extrapolate the approval to other indications as well.

The orirituximab biosimilarginal 351(k) application by Celltrion in April 2017 resulted in a complete response letter from the FDA. The rejection for this rituximab biosimilar cited multiple deficiencies, including “clinical, product quality, and facility” problems, as well as clinical study issues from the original submission.

According to the FDA reviewers, “In considering the totality of the evidence, the data submitted by [Celltrion] show that CT-P10 is highly similar to US-licensed Rituxan®, notwithstanding minor differences in clinically inactive compounds, and support a demonstration that there are no clinically meaningful differences between CT-P10 and US-licensed Rituxan in terms of safety, purity, and potency of the product.”

BR&R will cover the Oncology Drug Advisory Committee meeting and provide updates on its decision. If this rituximab biosimilar is eventually approved by the FDA, Teva would market the product in North America, based on a previous partnership agreement.

In other biosimilar news…Merck has inked an exclusive contract to supply its biosimilar infliximab (Renflexis®) with the US Department of Veterans Affairs. According to a report from Pharmaphorum, it will be the only infliximab biosimilar on the VA’s national formulary.

FDA Advisory Committees on Biosimilar Applications: Mylan’s Latest Muddies the Waters Further

When the Food and Drug Administration (FDA) approved the first biosimilar pegfilgrastim (Mylan’s Fulphila™), it broke precedent in more ways than one. Not only was this the first biosimilar member of the pegfilgrastim class to be approved, but its approval did not require an FDA Advisory Committee recommendation.

The FDA has been a bit fuzzy with respect to when an FDA Advisory Committee will be necessary. In the past, however, these AdComms had been required for all first biosimilar approvals to a new reference product. This was the case for filgrastim, infliximab, etanercept, trastuzumab, bevacizumab, adalimumab, and epoetin. Second biosimilars did not always require an AdComm, most recently last September with Boehringer Ingelheim’s Cyltezo®, the second adalimumab approved by FDA.

FDA Advisory CommitteeVarious problems with the 4 pegfilgrastim biologic license applications and resubmissions have provided the FDA ample time to review data and mull the consequences of approval or rejection. This case could be an exception. A greater challenge may be upcoming though.

Not that a great deal was achieved with the biosimilar AdComms. In general, votes for recommended approvals have been unanimous or lopsided. A recommendation for approval does not always result in approval—sticky manufacturing issues have gotten in the way (e.g., for Pfizer’s Retacrit). The FDA Advisory Committee meetings does give the public and other stakeholders a chance to air their views. Generally, this has been not for or against the biosimilar being reviewed but for or against biosimilars as a whole.

In March, I raised the case of Adello Biologics, which is attempting to gain approval of its filgrastim biosimilar without any phase 2 or phase 3 clinical data. This may be the second filgrastim biosimilar approved, so the FDA can avoid an AdComm on this basis. More importantly though, this agent could be the first biosimilar approved without any patient-based clinical testing (phase 1 is usually conducted in healthy volunteers). The next FDA Blood Products AdComm is not scheduled until November 29, 2018, and we do not know if Adello’s product will be part of that discussion. With a submission date of September 2017, one would expect a decision from FDA in the third quarter of this year.

In other biosimilar news… Celltrion resubmitted its 351(k) application to the FDA for its biosimilar version of trastuzumab. The original application resulted in an April 5 complete response letter for the Celltrion/Teva team.

A Test for Adello and for FDA’s Biosimilar Approval Pathway

We are on the verge of a few eagerly awaited decisions by the Food and Drug Administration (FDA). Celltrion and its partner Pfizer expect to hear news on their trastuzumab biosimilar in April, as does Celltrion separately on its rituximab biosimilar. These should make a significant impact on the evolution of biosimilars in the US and on marketshare penetration, but the FDA’s decision around the fourth filgrastim agent from a lesser- known player could be even more important to the industry.

One of the critical areas that differentiate 351(k) from 351(a) biologic licensing applications (BLAs) is that the FDA has emphasized the primary importance of evidence supporting the pharmacokinetic, pharmacodynamic, and structural similarity of the biosimilar to the originator product. In comparison, the standard BLA requires a sufficient catalog of data from phase 1, 2, and 3 clinical trials that point to the efficacy and safety of the biologic. To many in the biosimilar field, the inverted pyramid illustration left is very familiar.

351(k) biosimilar approval requirements

To date, the biosimilars brought to the application or registration process have been evaluated on their physiochemical characterization as well as the results of phase 2 and/or 3 clinical trials in at least one target indication. This is where it becomes interesting: Adello Biologic’s 351(k) application for filgrastim comprises the physiochemical biosimilarity evidence, but in terms of clinical data, only phase 1 studies were performed. That is, these studies included healthy volunteers only. And the studies further demonstrated the comparable pharmacokinetics and pharmacodynamics of this biosimilar and Neupogen®, the originator G-CSF drug.

This decision was not made in a vacuum. The manufacturer consulted with the FDA, as all prospective biosimilar makers do, on the requirements of their data packages. And the FDA accepted the application in September 2017. This fits with the agency’s policy to place ever-increasing weight on the physiochemical data as part of its “totality of evidence” approach. In its 2015 guidance, the FDA stated, “As a scientific matter, a comparative clinical study will be necessary to support a demonstration of biosimilarity if there is residual uncertainty about whether there are clinically meaningful differences between the proposed product and the reference product based on structural and functional characterization, animal testing, human [pharmacokinetic and pharmacodynamic] data, and clinical immunogenicity assessment.” With Adello’s filgrastim, one assumes that the FDA made the decision that the studies in healthy volunteers was sufficient.

Since Adello would be the second filgrastim biosimilar approved (also the fourth filgrastim on the market), the FDA may decide to dispense with an Advisory Committee meeting to discuss publicly the merits and issues with the agent. However, because this could be the first biosimilar approved without phase 2 or 3 clinical data, the FDA may decide on a conservative course, allowing the clinical community and the public to weigh in.

One could see how the lack of clinical data in actual patients will give pause in an Advisory Committee session. A patient undergoing cancer chemotherapy will likely have a different immunologic status, it can be argued, which may result in immunogenicity problems in real-world use. For agents already marketed in Europe, such issues may be absent and can be considered as part of the totality of evidence. Adello, however, does not market their biosimilar elsewhere.

Even if the Advisory Committee does not recommend (or a slight majority recommends) approval, the FDA could decide to license the drug anyway, in view of its stated policy to get biosimilars to market more rapidly. If this is the case, it would help ensure that R&D costs remain as low as possible for prospective biosimilar manufacturers, without the requirement of performing expensive phase 2 or 3 trials.

The question of whether an Advisory Committee will be held is still unknown. In response to queries, an FDA spokesman offered that the agency had “previously articulated a general expectation that a proposed biosimilar to a given reference product would be discussed at an Advisory Committee meeting if a proposed biosimilar to that reference product had not previously been discussed at an AC meeting. Subsequent proposed biosimilars to a given reference product may also be discussed at an AC meeting if FDA determines that there are specific issues to discuss.” In other words, no one knows. A query to Adello was not answered as of the publication of this article. Any updates will be noted in this space.

 

FDA Approves New Humira Biosimilar, Bypasses Advisory Board Route

Boehringer Ingelheim Pharmaceuticals, Inc. announced August 29 that it had received approval from the Food and Drug Administration (FDA) for its first biosimilar. Named Cyltezo™ (adalimumab-adbm), a biosimilar to Humira®, it is approved for several autoimmune disorders, including rheumatoid arthritis, polyarticular juvenile idiopathic arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease in adults, plaque psoriasis, and ulcerative colitis.

The FDA approval bypassed the need for an Arthritis Advisory Committee review and recommendation, which the agency suggested may be increasingly common with future biosimilar approvals. One suspects that this is more likely with the licensing of the first biosimilar for a particular originator product, with the assumption of a comprehensive data package on submission.

Like Amgen’s Amjevita®, Boehringer’s biosimilar will likely enter a holding pattern until patent litigation is settled (or the patents expire) on AbbVie’s Humira. In the meantime, Boehringer indicated that it will seek approval for an autoinjector, to stand alongside its newly approved subcutaneous formulation.

Boehringer has also applied for approval with the European Medicines Agency, which is expected to decide on its approval before the end of this year. Samsung Bioepsis and partner Biogen earned its own European approval for Imraldi™ this week, another adalimumab biosimilar.

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.

Two New Trastuzumab Biosimilars Submitted for FDA Approval

The team of Mylan and Biocon may have some company in the biosimilar competition for Herceptin® (trastuzumab). Two additional partnerships announced the filing of their 351(k) applications for trastuzumab biosimilars.

Amgen and Allergan are hoping ABP 980 will have smooth sailing through the approval system. The phase 3 study in patients with early-stage HER2-positive breast cancer was completed in January 2017, with study results reported in July 2016. This study enrolled 725 patients, and yielded positive results in terms of safety, efficacy, and similarity to the originator product.

Celltrion submitted their product application for CT-P6 (Herzuma™) to the FDA on July 30 as well. Its partner Teva will distribute and market the product in the US, upon approval. The phase 3 study for this product is ongoing, but the results of the primary outcome data from 549 patients were published in June 2017. The outcomes were found to be similar to those of Herceptin.

Mylan and Biocon had submitted their biosimilar version on November 1, 2016. The FDA Advisory Committee reviewing their product gave it their unanimous support on July 13, and the final FDA decision is expected by September 3, 2017. If approved, Mylan will have at least a 9-month time advantage to get their foot in the door of a $2.6 billion trastuzumab marketplace.

This sets up a very interesting pricing dynamic. I had originally thought that this scenario might occur first with adalimumab after the patent litigation was resolved, but it is very possible that multiple biosimilars for trastuzumab may be launched first and in a very short timeframe.

Assuming Mylan gets the nod from FDA first, they have a couple of obvious paths they can travel: (1) launch with a substantial discount in an attempt to capture as much marketshare as possible before the other market entrants arrive or (2) launch with a modest (but attractive) discount in an effort to maximize their revenue while their product remains the sole biosimilar available. It will then be a guessing game as to how Amgen/Allergan and Celltrion/Teva play their turns in this poker game. With sudden market competition, such as their launches could potentially pose, payers may play a bit of a waiting game themselves, to see where the chips fall.

FDA Advisory Committee Unanimously Recommends Approval for Avastin® and Herceptin® Biosimilars

It was a good day for biosimilar manufacturers and a bad day for Roche and its Genentech unit. Following a broadly positive FDA staff review of the first products to directly treat tumors, the Food and Drug Administration’s Oncology Drug Advisory Committee took the expected step of unanimously recommending approval for agents from Amgen and Mylan.

In the morning session, Amgen and Allergan’s ABP-215 was convincingly presented as equivalent to Roche’s bevacizumab (Avastin®), based on  pharmacologic, pharmacokinetic, efficacy, and safety evaluations. Clinical studies were performed in patients with non–small cell lung cancer. The Advisory Committee voted 17-0, recommending approval of the drug for all of the originator product’s nonprotected indications:

  • As first- or second-line treatment of patients with metastatic carcinoma of the colon or rectum in combination with intravenous 5-fluorouracil-based chemotherapy
  • Combined with fluoropyrimidine-irinotecan- or fluoropyrimidine-oxaliplatin-based chemotherapy, for the second-line treatment of patients with metastatic colorectal cancer who have progressed on a first-line ABP 215-containing regimen
  • As first-line treatment of unresectable, locally advanced, recurrent or metastatic nonsquamous non–small cell lung cancer in combination with carboplatin and paclitaxel
  • For the treatment of glioblastoma with progressive disease in adult patients following previous therapy as a single agent
  • For the treatment of metastatic renal-cell carcinoma in combination with interferon alfa
  • In combination with paclitaxel and cisplatin or paclitaxel and topotecan for the treatment of persistent, recurrent, or metastatic carcinoma of the cervix

Several questions brought up by the Committee involved the glioblastoma indication, and the drug’s passage over the blood–brain barrier. Progressive multifocal leukoencephalopathy was also mentioned, but this did not deter the Committee from its unanimous vote.

Amgen did not apply for approval for Avastin’s other orphan indications, which are “protected,” according to FDA. If they did want to obtain approval for those, an additional data package would need to be submitted.

Immunogenicity studies did not reveal any material differences between the biosimilar and originator product. In a minor twist, Amgen did the clinical testing of its biosimilar against the EU-licensed version of Avastin, and it had to conduct bridging studies to demonstrate the similarity between the EU version and the US-licensed originator drug.

In the day’s second session, Mylan’s MYL-1401O, a biosimilar version of Roche’s Herceptin (trastuzumab), was evaluated. The totality of evidence, according to the FDA staff review documents, supported the 351(k) application by Mylan. The Advisory Committee agreed, voting 16-0 to recommend the biosimilar for approval for use in Herceptin’s indications:

  • For use as adjuvant treatment of HER2 overexpressing node- positive or node-negative (ER/PR negative or with one high risk feature) breast cancer (1) as part of a treatment regimen consisting of doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel; (2) with docetaxel and carboplatin; or (3) as a single agent following multimodality anthracycline-based therapy
  • In combination with paclitaxel for first-line treatment of HER2-overexpressing metastatic breast cancer
  • As a single agent for treatment of HER2-overexpressing breast cancer in patients who have received one or more chemotherapy regimens for metastatic disease
  • In combination with cisplatin and capecitabine or 5- fluorouracil, for the treatment of patients with HER2 overexpressing metastatic gastric or gastroesophageal junction adenocarcinoma who have not received prior treatment for metastatic disease.

The FDA usually accepts the recommendation of its Advisory Committees in issuing final decisions. However, in late June, the agency rejected Pfizer’s Retacrit despite a 14–1 Advisory Committee vote to recommend, based on potential problems at a manufacturing facility. Mylan’s manufacturing partner Biocon, has recently been cited by French inspectors in connection with its European approval application, for potential problems at its Bangalore plant.

A final FDA decision is expected for Amgen’s bevacizumab biosimilar by September 14, and for Mylan’s trastuzumab biosimilar by September 3.

FDA Stuns With Rejection of Pfizer’s Retacrit

Following a 14-1 vote by its Oncology Drug Advisory Committee last month to recommend approval for Pfizer’s biosimilar version of Epogen®, the Food and Drug Administration (FDA) on June 22 sent the drug maker a complete response letter outlining its decision to reject the product.

It is unusual for the FDA to decide against a clear majority recommendation by its Advisory Committee, but the agency pointed to potential manufacturing issues at one of Pfizer’s facilities. Pfizer stated, “This [complete response letter] relates to matters noted in a Warning Letter issued on February 14, 2017 following a routine [FDA] inspection of the company’s facility in McPherson, Kansas in 2016. This facility was lisfdated as the potential manufacturing site in the BLA for the proposed epoetin alfa biosimilar. The issues noted in the Warning Letter do not relate specifically to the manufacture of epoetin alfa.” Although Pfizer responded to that notification by submitting a corrective and preventative action plan the following month, apparently, the FDA is not yet confident in the drug maker’s plan. According to Pfizer’s statement, the agency did not request that additional clinical data be submitted.

The FDA had cited this particular plant for several issues regarding the presence of foreign matter in medications being produced there. In its Warning Letter, the agency suggested there was “a significant loss of control in your manufacturing process” that represents a “severe risk of harm to patients.” The plant was one that Pfizer acquired in its purchase of Hospira in 2015.

This is Pfizer’s second rejection for Retacrit™, a product that was developed and brought to market in Europe by Hospira. Pfizer had resubmitted the 351(k) application in 2016.

The manufacturer stated that it is seeking to clear up any remaining issues at the plant cited by FDA. However, it is not clear whether Pfizer will have to resubmit its application entirely, as the rejection does not seem to be related to safety or efficacy issues involving the agent.

Pfizer’s Epogen® Biosimilar Gets FDA Advisory Committee Backing

Pfizer purchased Hospira in 2015, and one of its prizes was a biosimilar version of Epogen® and Procrit® that was already being reviewed by the Food and Drug Administration (FDA). The FDA rejected that 351(k) application and issued a complete response letter. Pfizer’s Hospira unit resubmitted its application for its Retacrit™ version of epoetin alpha in 2016. They received good news this week from the agency.

According to the FDA’s staffers’ summary released ahead of the May 25th Oncology Advisory Committee review, Retacrit fulfilled the requirements for biosimilarity. Today, the Advisory Committee added further support to this conclusion by voting 14-1 to recommend approval for all extrapolated indications, despite some safety concerns expressed by committee members.

According to the staff review, “The totality of analytical data support the determination that ‘Epoetin Hospira’ is highly similar to US-licensed Epogen/Procrit notwithstanding minor differences in clinically inactive components.” Nor were any clinically meaningful differences in immunogenicity risk found. The FDA staff review documents also concluded that Retacrit’s biosimilarity evidence supports extrapolation across its intended indications.

Last month, the Food and Drug Administration removed the Risk Evaluation and Mitigation Strategy (REMS) on the originator product, indicating that it is no longer necessary to “ensure that the benefits of Epogen/Procrit and Aranesp® outweigh the risks of shortened overall survival and/or increased risk of tumor progression or recurrence, for the treatment of anemia associated with myelosuppressive chemotherapy.” The originator agent has been linked with cardiovascular safety concerns, which has affected utilization of epoetin alpha over the years.

The first epoetin biosimilars were approved for use in Europe in 2007; a tremendous amount of real-world data have accumulated on their use. However, the FDA Oncology Advisory Committee cannot consider this in their decision.

Members of the FDA Committee expressed “residual concerns with immunogenicity and safety.” For example, patients with chronic kidney disease who require hemodialysis may have a reduced response to Retacrit.

The rather unique “dual” originator products (Epogen/Procrit) resulted from a duel in the 1990s between Amgen and Johnson & Johnson. Amgen originally manufactured the product in the late 1980s and licensed it to J&J’s Ortho Biotech unit. A stormy relationship developed, with lawsuits passed back and forth. The result was a licensing agreement that the drug would be manufactured under license (sounds a bit like a biosimilar, doesn’t it?) by each company for different indications.