Combination Therapy with Adalimumab -Is it Helpful?

A recent study (JM Chalbhoub et al. Inflamm Bowel Dis 2017; 23: 1316-27) performed a systematic review and meta-analysis to examine the effectiveness of Adalimumab (ADA) combination therapy compared with monotherapy.  With infliximab (IFX), the SONIC study, showed that combination therapy with an immunomodulator (IMM) (azathioprine) improved response; combination therapy resulted in reduced immunogenicity, lower rates of infusion reactions, and higher IFX levels.

With the advent of widespread use of therapeutic drug monitoring, some have questioned the need for combination therapy with IFX.  The need for combination therapy for ADA is also a matter of debate.  ADA has less immunogenicity than IFX and it is unclear if combination therapy will improve outcomes. There have been conflicting studies regarding combination therapy with ADA, prompting the current meta-analysis.

The authors identified 24 articles for inclusion from an initial pool of 1194. Key findings:

  • No significant difference between combination therapy and monotherapy was noted for induction of remission (OR 0.86) or response (OR 1.01). The induction of remission is based on data from 3096 patients (1400 on combination treatment).
  • No difference was noted for maintenance of remission (OR 0.97) or response (OR 0.91). The maintenance of remission is based on data from 1885 patients (859 on combination treatment).
  • Patients receiving combination therapy had lower odds of developing antidrug antibodies (OR 0.24)
  • Subgroup analysis in anti-TNF experienced patients showed improved successful induction of remission (OR 1.26) but also more frequent opportunistic infections (OR 2.44)

Overall, the authors conclude that “combination of ADA and immunomodulators does not seem superior to ADA monotherapy for induction and maintenance of remission and response to Crohn’s disease.” They do comment on the recent DIAMOND study which was a randomized open-label top-down strategy trial in anti-TNF-naive and IMM-naïve patients.  While no overall advantage of combination therapy was evident, better endoscopic response (84% vs. 64% with monotherapy) was seen at 26 weeks (but not at 52 weeks).

This study has several limitations.  Overall, there were a small number of randomized trials and the trials had significant heterogeneity.

My take (borrowed from authors): “It is unclear whether the addition of IMM impacts the efficacy of a less immunogenic anti-TNF biologic such as ADA in CD.” Though, in the subgroup of anti-TNF exposed patients, “combination therapy was associated with higher odds of induction of remission.”

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Adalimumab Can Reverse Growth Failure in Pediatric Crohn’s Disease

In an industry-sponsored study (TD Walters et al. Inflamm Bowel Dis 2017; 23: 967-75), adalimumab (ADA) was shown to be effective agent in reversing growth failure associated with pediatric Crohn’s disease (CD).

Background:  About one-third of children and adolescents with CD suffer from growth failure and delayed puberty.  Several prior studies have shown that anti-TNF therapy can improve height velocity and that early treatment with anti-TNF therapy (≤3 months after diagnosis) leads to greater improvement in height obtained, if initiated before puberty or early into puberty. This study examines the effectiveness of ADA in children from the IMAgINE 1 trial.

The authors identified 73 participants with growth delays (& adequate data) along with 27 participants with no growth delays.

Key findings:

  • ADA therapy significantly improved and normalized growth rates at 26 and 52 weeks in patients with baseline linear growth impairment.
  • At week 26, height velocity z-score was 1.33 among 23 children in remission compared with -0.78 (n=29) among “nonremitters”
  • At week 52, height velocity z-score was 2.17 among 27 children in remission compared with -1.57 (n=17) among “nonremitters”

My take: In moderate to severe CD, anti-TNF agents have been demonstrated to reverse growth failure; though, this is expected to occur only in patients with clinical response. To my knowledge, no other CD medical therapies have been proven to reverse growth failure (surgical treatment can improve growth as well).

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Quiet Spot on U Chicago Campus

Hepatitis B Reactivation Due to Immunosuppressive Therapies

The topic of Hepatitis B virus (HBV) reactivation has been discussed on this blog before (see link below).  Another excellent review on this topic (R Lomba, TJ Liang. Gastroenterol 2017; 152: 1297-1309) has been published.  The authors examine the course and mechanisms of HBV reactivation.  They divide the risk of reactivation into three groups: high, moderate and low risk and proposed management.

High risk groups, which have >10% risk of reactivation) include the following

  • B-cell-depleting agents including rituximab, ofatumumab, alemtuumab, and ibritumumab
  • High-dose corticosteroids (>20 mg/day in adults)
  • Antracyclines including doxorubicin
  • Potent TNF-α inhibitors: infliximab, adalimummab, certolizumab, and golimumab
  • Local therapy ofr HCC including TACE (transarterial chemoembolization)

Moderate groups (1-10% reactivation) include cytokine-based Rx (eg. abatacept, ustekinumab, natalizumab, vedolizumab), cyclosporine, systemic chemotherapy, moderate corticosteroid dosing

Low risk groups (<1% reactivation) include thiopurines (azathioprine, 6-mercaptopurine), and methotrexate as well as short-term low-dose corticosteroids.

Management:

  • For HBV screening, the authors recommend HBsAg and anti-HBc testing
  • Prophylactic therapy with potent oral anti-HBV therapies are recommended for those at moderate or high risk of reactivation.  In those at low risk, the options include prophylactic treatment or watchful monitoring.
  • A more detailed algorithm is provided in Figure 3.  In those with HBsAg positivity, if HBV DNA is less than 2000 U/mL, this algorithm suggests monitoring labs (HBsAg, ALT, HBV DNA every 3 months)

Mechanisms of HBV reactivation are discussed.  For example, with TNF-α inhibitors “can activate a unique host antiviral pathway, the APOBEC (apolipoprotein B mRNA editing enzyme, catlytic polypeptide-like) proteins, that cause the degradation of cccDNA in HBV-infected cells. Thus, blocking this endogenous antiviral pathway may lead to a higher HBV replication state and HBV reactivation.”

My take: In pediatric gastroenterology, we do not see a lot of HBV reactivation. Nevertheless, we do use many of the medications which can trigger HBV reactivation and need to keep these recommendations in mind.

Related blog post: What HBV Testing is Needed Before TNF Inhibitor Therapy

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Surgical Reset for Anti-TNF Therapy with Crohn’s Disease

A recent study (A Assa et al. Inflamm Bowel Dis 2017; 23: 791-97) indicates that after surgery, anti-TNFα treatment is worth another try.

In this retrospective study with 53 children, 18 had “pharmacodynamic failure” with anti-TNFα medications (PK group) and 35 were controls. “Phamacocynamic failure is characterized by either a lack of improvement of CD symptoms or  loss of response after initial improvement in the setting of adequate serum drug levels without ADAs” [antidrug antibodies].

Key findings:

  • Mean age at time of intestinal resection was 14.8 years
  • Median time from resection to anti-TNF initiation was 8 months
  • Compared to the control group, the PK group had similar response to anti-TNF therapy.   “Similar proportions of patients from both groups were in clinical remission on anti-TNF treatment after 12 months and at the end of follow-up (1.8 years)”
  • At 12 months, remission rates were 89% (PK) versus 88.5% (control)

The authors propose an explanation: “A plausible explanation for this finding is that in severely inflamed tissue with high inflammatory burden, local high levels of TNFα serves as a sink for anti-TNFα antibodies and that tissue injury and local hypoxia might further limit drug penetrance to its target.”

My take: This information is useful.  Many patients who have surgery may respond to anti-TNFα therapy subsequently.  The unanswered question: Could more frequent dosing of anti-TNFα therapy have averted surgery in some patients by overcoming areas of intense disease?

 

Safety of Long-term Adalimumab in Pediatrics; Weighted PCDAI

A recent study (W Faubion et al. Inflamm Bowel Dis 2017; 23: 453-60) reports on the long-term safety/effectiveness of Adalimumab in pediatric patients entering the IMAgINE 2 trial (& who completed the 52 week IMAgINE 1 trial).

Patients with a PCDAI <10 were considered to be in remission and those who had a drop in PCDAI of 15 or more were considered to have had a treatment response.

Key findings:

  • Of the 100 patients enrolled in IMAgINE 2, 41% achieved remission and 48% had a treatment response at week 240.
  • >80% of patients were “able to discontinue use of corticosteroids.”
  • Adalimumab treatment was associated with growth normalization.
  • No new safety signals were identified.

While this study provides some reassurance regarding long-term adalimumab use, it should be noted that the instruments used to assess efficacy in this trial (& many others) are suboptimal.

A recent study (D Turner et al. JPGN 2017; 64: 254-60) showed that PCDAI (and several similar versions) had “poor correlation with calprotectin” and none of the PCDAI versions “can give a valid assessment of mucosal healing.”  This study had used prospectively collected data from the ImageKids study of 100 children with Crohn’s disease.  For the weighted PCDAI, the “best cut-off to identify endoscopic mucosal healing was <12.5 points” with a sensitivity of 58% and specificity of 84%.\

wPCDAI:

History: (recall 1 week):

  • Abdominal Pain  0=None, 10=Mild (does not interfere with activities, brief), 20=Moderate/Severe
  • Patient functioning 0=No limitations, 10=Occn difficulty with activities (below par), 20=frequent limitations
  • Stools per day 0=0-1 liquid stools, no blood, 7.5=up to 2 semiformed stools with blood or 2-5 liquid nonblood, 15=Gross bleeding or ≥6 liquid stools or nocturnal diarrhea

Laboratory

  • ESR 0 points if <20, 7.5 points if 20-50, 15 points if >50
  • Albumin 0 points if ≥3.5 g/dL, 10 points if 3.1-3.4 g/dL, and 20 points if ≤3.0 g/dL

Examination

  • Weight 0= Weight gain or stable or voluntary weight loss, 5=involuntary weight loss 1-9% or involuntary weight stable, 10= weight loss ≥10%
  • Perirectal Disease 0=None or asymptomatic tags, 7.5= 1-2 indolent fistula, scant drainage, no tenderness, 15=active fistula, drainage, tenderness or abscess

Extraintestinal Manifestatons: Fever for 3 days (≥38.5), definite arthritis, uveitis, erythema nodosum, or pyoderma gangrenosum

  • Points: 0=None, 10 ≥1

Total Score 0-125: ______________________

As compared with PCDAI, the weighted PCDAI drops height velocity, abdominal examination, and hematocrit.  Turner et al note “their exclusion does not mean that they have no role in reflecting disease activity, but that the other included items, as a whole, are inclusive of the contribution of the 3 items.” Also, the weighted PCDAI simplifies the “extraintestinal manifestation” into a simple choice; overall, this affects few scores due to the low frequency of these manifestations.

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FDA approves Amjevita (Humira biosimilar)

On 9/23/16: FDA approved Amjevita (Humira biosimilar)

Excerpt:

The U.S. Food and Drug Administration today approved Amjevita (adalimumab-atto) as a biosimilar to Humira (adalimumab) for multiple inflammatory diseases.

Amjevita is approved for the following indications in adult patients:

  • moderately to severely active rheumatoid arthritis;
  • active psoriatic arthritis;
  • active ankylosing spondylitis (an arthritis that affects the spine);
  • moderately to severely active Crohn’s disease;
  • moderately to severely active ulcerative colitis; and
  • moderate to severe plaque psoriasis.

…Amjevita is biosimilar to Humira. It has been approved as a biosimilar, not as an interchangeable product.

Fort Knox, Maine

Fort Knox, Maine

Safer Than You Think: Biologic Therapies for IBD and Risk of Infection and Malignancy

While there have been a number of studies which have highlighted the potential risks of biologic agents, many studies have NOT identified any risk of infection or malignancy.

Another recent systematic review/meta-analysis (S Bonovas et al. Clin Gastroenterol Hepatol 2016; 14: 1385-97) provides reassuring data regarding the following biologics: infliximab, adalimumab, certolizumab, golimumab, natalizumab, and vedolizumab.

The authors identified 49 randomized placebo-controlled studies with 14,590 participants.

Key findings:

  • There was a moderate infection risk with odds ratio of 1.19 (19% increase in odds of developing an infection) and significant increase in opportunistic infections (eg. tuberculosis) OR 1.90
  • Risk of serious infections was NOT increased in patients treated with biologics with OR 0.89.  In studies with low risk of bias, the risk of serious infections had OR of 0.56.
  • No increase in malignancy risk was identified with OR 0.90 but the authors note that data was insufficient in terms of exposure and follow-up to be conclusive.

The authors note that the studies including in this review challenge some of the findings of observational studies. “However, observational studies lack the experimental random allocation of participants…the discrepancies between observational studies and randomized trial evidence might be explained by the inability of observational designs to fully address the complex and important differences between the IBD patients receiving and those not receiving biologics.”

Study limitations include “sponsorship bias -because the trials were supported by pharmaceutical companies and limited followup of 24 months. In addition, most of the trials in the meta-analysis were judged to be at high or unclear risk of bias because of their methodological characteristics.

My take: This study indicates that biologic therapies do not appear to increase the risk of serious infections and may not increase the overall risk of malignancy.

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Portland Fish Market

Portland Fish Market