Interchangeability, Immunogenecity and Infliximab Biosimilars

A recent study (G Fiorino et al. IBD 2018; 24: 601-6, editorial by KH Katsanos et al 465-6) provides more data on “full interchangeability” in regards to infliximab (IFX) and biosimilars CT-P13 and SB2. Full abstract below.

Key finding in study:

  • Antibodies to infliximab (ATI) cross-reacted with any type of IFX or IFX-biosimilar

Points from the editorial:

  • “The landmark NOR-SWITCH randomized controlled trial showed that 1-time switching from RMC [Remicade] to CT-P13 is not inferior to continued treatment with the infliximab originator…there are no data regarding multiple switches…Consequently, cross-switching (switching between 2 biosimilars), reverse switching (switching from biosimilar to its originator) or multiple/repeated switching is not currently recommended.”
  • This study, however, shows that “if you have already developed antibodies to 1 infliximab product, there is no point in switching to another infliximab product.”

Abstract:

BackgroundInfliximab (IFX) biosimilars CT-P13 and SB2 have comparable efficacy, safety, and immunogenicity to the originator Remicade (RMC). However, concerns about cross-switching patients between the 3 brands were raised in the absence of cross reactivity data between them. We aimed to determine whether antibodies to infliximab (ATI) in inflammatory bowel disease (IBD) patients cross-react with RMC, CT-P13, and SB2.

MethodsBased on previous ATI status, samples from 34 patients participating in the BIOSIM01 study (13 RMC, 9 CT-P13, and 12 switchers) were selected. Patients were treated with either RMC only, or CT-P13 only, or with RMC switched to CT-P13. Additionally, 28 IFX-naïve patients were assayed as controls. In total, 180 samples were analyzed. ATI trough levels were measured in parallel with 3 different bridging Enzyme Linked Immunosorbent Assays constructed using the 3 drugs. Spearman’s coefficient and percentages of agreement were used to study the correlation between each assay.

ResultsIn total, 76 samples out of 152 IFX-treated patient samples were ATI-positive (30 RMC, 14 CT-P13, and 32 switchers). All resulted ATI-positive when either CT-P13 or SB2 bridging assays were used. The overall percentage of agreement was 100% when compared either with CT-P13 or SB2 assays. No significant differences were found among ATI levels and coefficients (Spearman’s 0.98 to 1.0, P < 0.0001).

ConclusionsATI of RMC-treated, CT-P13-treated or RMC to CT-P13 switched patients show full cross-reactivity with CT-P13 and SB2. Findings suggest that immunodominant epitopes in the reference and CT-P13 drugs are equally present in SB2. Data support full interchangeability between biosimilars in regard to immunogenicity.

My take: In patients doing well with IFX, switching to a biosimilar is not currently recommended.  In patients naive to IFX, use of IFX or biosimilar is expected to have similar efficacy.

Related study: B Kang et al. IBD 2018; 24: 607-16.  This prospective study of 36 pediatric patients did not identify any significant differences in efficacy…or immunogenicity after switching from IFX to CT-P13.

Related blog posts:

IBD Shorts -March 2018

T Piester et al. Inflamm Bowel Dis 2018; 24: 227-34.  Stanford group published data on 49 patients which highlight the utility of a point of care (mobile) infliximab (IFX) dosing calculator: http://med.stanford.edu/gastroenterology/infliximab-calc/  In their cohort, the IFX calculator recommendations were for IFX dosing escalations in 13% of the 222 calculations.  Overall, the IFX calculator was part of a larger quality initiative (QI) to achieve therapeutic drug levels >5 mcg/mL which occurred in 81% during the QI period.

JC deBruyn et al. JPGN 2018; 66: 268-77. This was a retrospective review of infliximab (IFX) in pediatric Crohn’s disease with 180 children. The authors determined that IFX had good therapeutic durability with 91% remaining on IFX after 2 years of treatment.

FS Macaluso et al. Inflamm Bowel Dis 2018; 24: 394-401. In this 2-year study, among 630 patients, 46 had a modestly-dosed immunomodulator added to anti-TNF therapy due to loss of response (31 to IFX or biosimilar, 10 with adalimumab, and 5 with golimumab).  This resulted in a steroid-free remission in 15 (32.6%) and a clinical response in 6 (13.0%). The immunomodulators were azathioprine in 15, 6-mercaptopurine in 5, methotrexate in 20, and mycophenolate mofetil in 6. The median doses for immunomodulators were 1.64 mg/kg/day, 0.84 mg/kg/day, 15.6 mg/week, and 1500 mg/day respectively.

C Reenaers et al. Clin Gastroenter Hepatol 2018; 16: 234-43. This retrospective study examined 7-year outcomes from a STORI cohort of 115 adults with Crohn’s disease (CD) with combination therapy who had infliximab withdrawal after achieving sustained remission. Among those restarting infliximab, treatment failed in 30.1%; 70.2% “had no failure of de-escalation strategy.” Major complicatins occurred in 18.5% of patients. Risk factors for failure included anemia (Hgb <12.5), increased white blood cell count >5.0, and upper GI location of CD.

VM Merrick et al. JPGN 2018; 66: 274-80.  This UK “real-life” review of 37 centers and 524 patients (429 with Crohn’s disease) found a remarkably poor rate of documentation.  They could determine the remission rates in only 71 of these patients (65% 46 of 71).  Thus, in the real-world, presumably in adults and children, most institutions do not know their remission rates.  While the determination of remission still relies on imperfect measures, the centers who participate in ImproveCareNow have high documentation rates –this is also a real-world experience as more than 29,000 patients and more than 900 pediatric GI doctors participate.

Paris Classification Quiz and Explanation

At one of our ImproveCareNow population management meetings, Dr. Chelly Dykes reviewed the Paris Classification and frequent misconceptions in using this system.  To illustrate this point, I am going to post 6 Quiz Slides and then follow that with the answers and explanation.  These quiz slides were derived from previous ImproveCareNow community meetings.

Answers:

  1. A
  2. B (macroscopic disease counts –erythema alone does not count)
  3. A (macroscopic disease counts)
  4. B (not ileum only unless colonic disease extends beyond cecum)
  5. F (though B acceptable)
  6. F (though B acceptable)

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Briefly noted: Mongersen, Aprepitant, and Anesthetic Outcomes

BG Feagan et al. Gastroenterol 2018; 154: 61-4.  In this study of GED-0301 (Mongersen), an antisense oligodeoxynucleotide affecting Smad7, was randomly assigned to 63 patients with Crohn’s disease (160 mg/day).  Endoscopic improvement was observed in 37%  at week 12. Clinical remission (CDAI<150) was noted in  32% (4 weeks of Rx), 35%  (8 weeks of Rx) and 48% (12 weeks of Rx). No new safety signals were noted.

Related blog posts:

PJ Pasricha et al. Gastroenterol 2018; 154: 65-76.  First of all, I have to say that I like the visual abstracts in many Gastro studies.  In this randomized, double-masked “APRON” study of 126 patients with chronic nausea or gastroparesis receiving Aprepitant, a neurokinin-1 receptor antagonist, or placebo, the key findings were the following:

  • Aprepitant did not reduce symptoms of nausea significantly compared to placebo
  • Apreptiant-treated patients had improvements in secondary outcomes of symptom severity for nausea (1.8 vs 1.0, P=.005 on Gastroparesis Clinical Symptom Index) and overall symptoms (1.3 vs. 0.7, P=.001)

Related blog post:

B Bielawska et al. Gastroenterol 2018; 154: 77-85. Using data (administrative databases) and propensity matching from more than 3 million outpatient colonoscopies (2005-2012), the authors noted that the use of anesthesia assistance (AA) was associated with an increased risk of aspiration pneumonia (OR 1.63) but not perforation (OR 0.99). Though this study is limited by its retrospective design and reliance on administrative data, the authors state “the potential for residual confounding by indication for AA [is] extremely unlikely, especially because AA use in Ontario appears to be driven by institutional policy or business model rather than by patient factors.”

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Bright Angel Trail

Iron Metabolism Improves after Anti-TNF Therapy for Crohn’s Disease

A previous study has shown that low vitamin D levels improved with anti-TNF therapy for Crohn’s disease in the absence of supplemental vitamin D.  Similarly, a recent study (MA Atkinson, MB Leonare, R Herskovitz, RN Baldassano, MR Denburg. JPGN 2018; 66: 90-4) showed improvement in iron metabolism with anti-TNF therapy.

In 40 children and adolescents with Crohn’s disease, the authors measured serum hepcidin-25 and hemoglobin at baseline and then 10 weeks after anti-TNF therapy.

Key findings:

  • Median hepcidin concentrations decreased (27.9–>23.2 ng/mL) and mean hemoglobin increased (10.6–>10.9).
  • Disease activity and markers of inflammation also decreased.

My take: This study shows that improvement in inflammation is associated with meaningful improvement in anemia.  However, most patients will need additional treatment for anemia, particularly as anemia may be related to blood loss in addition to anemia of chronic disease/inflammation.

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Crohn’s Disease Diagnosis Identified After Colectomy in Presumed Ulcerative Colitis

A recent retrospective single-center study (I Jones et al. JPGN 2018; 66: 69-72) identified a high rate of inflammatory bowel disease (IBD) reclassification.  From 2003-2014, 570 children were diagnosed with IBD, including 190 with ulcerative colitis.  29 of these patients underwent colectomy.  Among this select group, 24% (7/29) were subsequently reclassified as having Crohn’s disease, sometimes several years later.  Only two of the seven reclassified patients were younger than 10 years of age at the time of colectomy.

My take: This rate of Crohn’s disease following colectomy is higher than in previous reports (generally 5-10%).  The larger point is that the diagnosis of ulcerative colitis is more uncertain in the pediatric population, particularly in those in the first decade of life.

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Near Bright Angel Trail, Grand Canyon

Increasing Cost/Use of Biologic Therapies for Inflammatory Bowel Disease

As noted in a previous blog post (Changes in the Use of IBD Biologic Therapy), there has been an increased use of biologic therapy early in the course of patient’s with inflammatory bowel disease (IBD). Another retrospective study (H Yu et al AP&T 2018; 47: 364-70 -thanks to Ben Gold for this reference) examines the market share and costs of biologic therapy for IBD using the Truven Marketscan Commercial Claims and Encounters database (2007-2015).  This database consists of out-patient and in-patient pharmaceutical claims of approximately 40-50 million privately insured patients each year from patients from all 50 states (U.S.).

Key findings:

  • Among 415,405 patients with IBD (188,842 with Crohn’s, 195,183 with ulcerative colitis, 31,380 with indeterminate IBD), the proportion using biologics increased over the 9-year period (2007-2015); overall, the market share increase was from 7.1% (2007) to 20.5% (2015).
  • There were 28,797 pediatric patients with IBD (17,296 with Crohn’s, 9368 with ulcerative colitis, and 2133 with indeterminate colitis). The overall market share in pediatric patients was the highest, increasing from 19.1% to 45.9%.
  • For all patients with Crohn’s disease (CD) the proportion receiving biologic therapy increased from 21.8% to 43.8%.  For patients with ulcerative colitis (UC), the proportion increased from 5.1% to 16.2%.
  • Per-member per-year (PMPY) costs increased. “The average biologic-taking patient accounted for $25,275 PMPY in 2007 and $36,051 PMPY in 2015.”  This was similar in the pediatric population, going from $23,616 PMPY in 2007 to $41,109 PMPY in 2015.
  • The share of costs of medicines: the costs of biologics as a share of the total increased from 72.9% in 2007 to 85.7% in 2015. 95% of the pharmacy costs in children with IBD are attributed to biologics.

My take: This trend of increasing use of biologics and their associated costs is going to continue due to their effectiveness. While there are direct costs related to these medications, the net cost is unclear as they can prevent hospitalizations and surgeries. In addition, by helping to spare corticosteroids and increasing response rates, biologic therapies improve quality of life, minimize opportunity loss, and optimize long-term health outcomes.

Bright Angel Trail, Grand Canyon

 

Ketchup Packet Ingestion–Crohn’s Disease Mimic

In the category of –“I have not seen that before”…

Link: NY Daily News Women diagnosed with Crohn’s disease actually had ketchup packet in her intestines for six years (Thanks to my son for pointing out this story)

An excerpt:

A woman believed she was suffering from Crohn’s disease for six years until doctors performed surgery and discovered a ketchup packet in the lining of her intestine.

The 41-year-old patient had symptoms consistent with the serious bowel disease — including acute abdominal pain and bloating lasting up to three days — but she did not respond to the standard treatments.

Case study reference: Visagan R, et al. BMJ Case Rep 2013. doi:10.1136/bcr-2013-009603

Related blog post: Add it to the list

 

CALM Study: Tight Control Improves Outcomes in Crohn’s Disease

A recent study (JF Colombel et al. Lancet 2017; http://dx.doi.org/10.1016/S0140-6736(17)32641-7 ) shows that “tight control” improves outcomes in Crohn’s disease.  This study was alluded to in a previous post: CCFA 2017 Updates (part 2)

Background: The CALM study was an open-label, randomized study.  122 adult patients were randomized to typical clinical management and 122 patients received “tight control” in which treatment was modified by fecal calprotectin (≥250 mcg/g) and CRP (≥ 0.5 mg/dL) values in addition to clinical symptoms.

Treatment was escalated in both groups in a stepwise manner.  Initial treatment was with adalimumab induction and then every other week. If patient did not meet treatment objectives, which differed in the groups, then adalimumab would be given every week, and then, if still needed, azathioprine would be added. Interestingly, both groups had ~25% of participants who were smokers which is known to worsen outcomes.

Key Findings:

  • Mucosal healing (CDEIS <4) was significantly improved in tight control group at week 48: 46% vs. 30%.
  • Similarly, steroid-free remission based on CDAI <150 was better in tight control group compared with standard treatment at week 48: 59.8% vs. 39.3%.  Endoscopic response was 50.8% compared with 40.2% respectively.

My take (1st part borrowed from authors): “Tight control of inflammation in patients with Crohn’s disease, with objective markers of disease activity  and clinical symptoms to drive treatment decisions, achieved better endoscopic and clinical outcomes than conventional care based on symptoms alone.” Yet, there are a large number who do not respond adequately and better treatments in these patients are needed.

As an aside, these response rates based on objective markers are far lower than the remission rates claimed by ImproveCareNow; thus, while ImproveCareNow is forward-thinking and helping improve outcomes with inflammatory bowel disease, we need to be careful about citing remission rate trends that are not directly linked to objective markers.

NY Times: Humira’s Best-Selling Drug Formula: Start at a High Price. Go Higher.

NY Times: Humira’s Best-Selling Drug Formula: Start at a High Price. Go Higher.

An excerpt:

Humira is the best-selling prescription drug in the world…The price of Humira, an anti-inflammatory drug dispensed in an injectable pen, has risen from about $19,000 a year in 2012, to more than $38,000 today, per patient, after rebates, according to SSR Health, a research firm. That’s an increase of 100 percent…

How much you actually pay out of pocket, and whether you can afford Humira at all, depend on your insurance and eligibility for discounts…

Humira, which accounted for nearly two-thirds of AbbVie’s $25.6 billion in revenue in 2016, was not simple to develop. It is among a new class of drugs known as biologics, which are made from living cells rather than synthetic chemicals…

Looking at the international picture tells its own story about drug costs. A prefilled carton with two syringes costs $2,669 in the United States, compared with $1,362 in Britain, $822 in Switzerland and $552 in South Africa…

An analysis by the Institute for Clinical and Economic Review found that Humira’s list price would need to be discounted by at least 55 percent to be cost effective for rheumatoid arthritis, its originally approved use.

Dr. Steven D. Pearson, the founder of the institute, which provides cost benefit data to health plans, said competing drugs were overpriced as well.

“Even in a space like this, where there is a lot of competition, we don’t see the prices coming down,” he said. “That speaks to the fact that it doesn’t often function like a free market usually would.”..

AbbVie joined a few of its rivals in saying it would limit price increases to single digits this year, and so only raised Humira by another 9.7 percent this month, roughly four and a half times the inflation rate. For the drug industry, that counts as generosity.

My take: Humira is a very important and effective medication, particularly for inflammatory bowel disease and rheumatoid arthritis. I infer from this article which compares the Humira pricing strategy to that used by Martin Shkreli that if U.S. consumers are to have more affordable pharmaceuticals, government intervention will be needed. AbbVie, like many other pharmaceutical companies, will continue to aggressively price Humira; after all, 8 billion in profits is not as good as 10 billion.

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