Safety Signal for Anti-TNFs

In a large population of inflammatory bowel disease patients, anti-tumor necrosis factor medications (anti-TNFs) did not increase the risk of cancer in a recent study from Denmark.  This link provides a summary of the study (JAMA 2014 June 17 [doi:10.1001/jama.2014.5613]) in GI & Hepatology News: Anti-TNFs -Safety Signal

Here’s an excerpt:

This study “assessed the risks of any cancer and 11 individual cancers, including malignant melanoma, in 56,146 IBD patients aged 15 and older…during 1999-2012, of whom 4,553 took TNF-alpha antagonists.  Median follow-up was 9.3 years…A total of 6.7% of the patients who never took TNF-alpha antagonists developed cancer during follow-up compared with 1.8% of patients who took the drugs…

Stratifying for cancer risk according to years since first exposure, no specific time-dependent pattern was observed in our study…an increased risk in the long term cannot be excluded.”

In another systemic review study (Clinical Gastroenterology and Hepatology Volume 12, Issue 9, Pages 1443–1451, September 2014) focused on pediatric IBD patients (n=5528), the authors found that “Two patients developed lymphoma (2.1/10,000 PYF). This value was … lower than the population of pediatric patients receiving thiopurine monotherapy (4.5/10,000 PYF; SIR, 0.47; 95% CI, 0.03–6.44)”…”the risk of lymphoma was no greater among children with IBD who received anti-TNF therapy than those treated with other IBD therapies or adults treated with anti-TNF agents. The rate of serious infection was significantly lower among pediatric patients with IBD treated with anti-TNF agents than those treated with steroids, or adults with IBD who received anti-TNF therapy.”  Here’s the link: anti-TNF therapy with lower lymphoma risk than thiopurines in pediatrics

Comparing Biologics for Ulcerative Colitis

A recent study has reviewed biologic therapies for ulcerative colitis (Ann Intern Med. 2014;160(10):704-711). Here’s the abstract link: bit.ly/1o5PpRX.

Data Synthesis: ..There were 7 double-blind, placebo-controlled trials that were rated as low risk of bias and showed that all biological agents (adalimumab, golimumab, infliximab, and vedolizumab) resulted in more clinical responses, clinical remissions, and mucosal healings than placebo for induction therapy. The results of network meta-analysis suggested that infliximab is more effective to induce clinical response (odds ratio, 2.36 [95% credible interval, 1.22 to 4.63]) and mucosal healing (odds ratio, 2.02 [95% credible interval, 1.13 to 3.59]) than adalimumab. No other indirect comparison reached statistical significance. For maintenance, 6 double-blind, placebo-controlled trials that were rated high risk of bias showed that all biological agents have greater clinical efficacy than placebo. The occurrence of adverse events was not different between biological agents and placebo.

Limitation: Few trials, no head-to-head comparisons, and inadequate follow-up in maintenance trials.

Conclusion: Biological agents are effective treatments for UC, but head-to-head trials are warranted to establish the best therapeutic option.

Related blog posts:

 

Infliximab Compared to Adalimumab -Which is Better?

Pharmaceutical companies are not motivated to provide a definitive answer on the title question.  A recent study (Clin Gastroenterol Hepatol 2014; 12: 811-17) states that “head-to-head clinical trials of anti-TNF therapies are unlikely to ever be undertaken because of the extreme cost to conduct such studies and the financial risk that such trials would entail for the manufacturers.”  The two most popular biologics, infliximab (IFX) and adalimumab (ADA), for inflammatory bowel disease have been incredibly successful (Multi-billion dollar biologics | gutsandgrowth).

The current study is “one of the first to directly compare the effectiveness” of IFX and ADA for Crohn’s disease.  The authors retrospectively examined a U.S. Medicare data cohort from 2006-2010 and identified new users with 1459 IFX and 871 ADA patients.  While 94% of Medicare enrollees are >65 years, this study had a range of patient ages due to those who received Medicare due to disability.  In fact, in the ADA group, ~60% were between 30-60 years and in the IFX group, ~44% were in this age group.

Key result:

  • After 26 weeks of treatment, 49% of patients receiving IFX remained on drug compared with 47% of those receiving ADA.
  • Fewer patients with IFX underwent surgery (5.5 vs 6.9 surgeries per 100 person-years) but this did not reach statistical significance.
  • Rates of hospitalization did not differ among the two groups

While persistence is an imperfect measure of effectiveness, the fact that surgeries and hospitalizations were similar indicates that the medications are likely to have similar clinical effectiveness, at least in this population.  Data on mucosal healing, more direct measures of effectiveness, and longer followup certainly would strengthen this conclusion.

Superiority of Anti-TNF Therapy (Part 2)

A recent blog (Superiority of Anti-TNF Therapy in Children | gutsandgrowth) described a recent article showing that kids treated with anti-TNF therapy at the time of diagnosis had improved outcomes compared to children who were treated with other medications.  In this day of multimedia, there is a video explaining the study which may be helpful for families and clinicians alike –here’s the link:  Dr. Michael Stephens discusses the research findings: .

An excerpt from the explanation with the video:

The current research study looks at outcomes and compares three different types of treatments. The first group receives anti-TNF therapy. The second group received immune modulating therapy. The third group received no treatment within the first three months. This study was an observational study and the choice of treatment was at the discretion of the physician. In order to correct for this factor, a statistical technique was used. Patients with similar characteristics were paired within the three groups . The results showed that patients who received the anti-TNF therapy had an improved outcome, such as a higher remission rate and some indications of improved growth, at one year. All three groups had improvements in weight and body mass index but only the anti-TNF group had improvements in linear growth.

Assessing and discussing risk of lymphoma in IBD

A recent article has shown that the absolute lymphoma risk from medications in children and young adults with IBD is quite low (Inflamm Bowel Dis 2012; 18: 838-43).

In this single center study from 1979-2008, 1374 pediatric IBD patients had charts reviewed to determine whether lymphoma developed.  In total, two male patients who had received thiopurines developed lymphoma (one Hodgkin, one anaplastic large cell) in 6624 patient-years of follow-up.  Both patients are alive after chemotherapy.  Mean follow-up was 4.8 years per patient.  The absolute lymphoma incidence rate was 3 per 10,000 patient-years; after thiopurine exposure, the rate was 4.5 per 10,000 patient-years compared to an expected 0.58 per 10,000 patient-years.

In this study, 22% of the patients had received TNF inhibitors.  None developed lymphoma.  The risk of biologics could not be fully assessed due to a limited study period: 713 person-years taking the medication.

The risk of thiopurine-associated lymphoma was similar to previous studies but did not reach statistical significance.  As related in other studies, the risk of biologic agents, like Remicade, Humira, and Cimzia, is heavily influenced by whether patients had also received immunomodulators.

One useful way to try to convey this risk has been with diagrams.  One useful diagram is a palette of one thousand people or of 10,000 people showing the absolute risk and one showing the risk for other complications like infection.  You can make your own by going to the following link:

Download Communication Tools

RiskComm

Additional references/blog entries:

Only one chance to make first impression

Biologics | Living Longer | Arthritis Today Magazine -From Arthritis magazine: biologics improve survival in Rheumatoid arthritis

TNF antagonists and UC

In my fellowship (15 years ago), the use of thiopurines (eg. azathioprine, 6-mercaptopurine) for ulcerative colitis was debated.  Many physicians urged colectomy rather than using these drugs which could have long-term consequences.  At the time, the risk of thiopurines was less well-understood.  Over time, the use of these agents has become common when mesalamine products were ineffective.  The same issue comes up with TNF antagonists versus colectomy.

A recent study provides more information on the effectiveness of adalimumab for patients with moderate-to-severe UC but does not settle this debate (Gastroenterology 2012; 142: 257-65).  In this study, termed ‘ULTRA-2’ (Ulcerative colitis long-term remission and maintenance with adalimumab 2), the  efficacy of adalimumab for induction & maintenance of remission was studied in 494 patients.  This was a randomized, double-blind, placebo-controlled study; average age was 40 years.

Clinical remission in the adalimumab group were 16.5% at 8 weeks (9.3% placebo).  At 52 weeks, 17.3% in the adalimumab group were in remission (8.5% placebo).  Among patients naive to anti-TNF agents, the response rate was 21.3% at week 8 & 22% at week 52.  Safety overall was similar in both groups; however, in the adalimumab group one patient developed gastric cancer and one developed squamous cell carcinoma.

The authors conclude that adalimumab is safe and more effective than placebo in inducing and maintaining remission among patients with moderate-to-severe UC.

A second study, also published this past month, looks at the use of infliximab for maintenance therapy for UC (Inflamm Bowel Dis 2012; 18: 201-11).  Patients who had achieved benefit from ACT-1 and ACT-2 studies were followed for three years.  Dosage of infliximab could be adjusted.  A total of 229 patients entered the study.  During the study, 70 patients (30.6%) discontinued infliximab due to adverse effects (10.5%), lack of efficacy (4.8%) or other reasons (15.2%); the majority were able to continue infliximab.  The authors indicate that no new safety issues were identified. Yet, there were two deaths among the infliximab group including a 19 year-old nonsmoker who developed lung cancer and a lethal case of histoplasmosis.

Because the improvement compared to placebo is modest with both of these agents, the question about whether to use these medications or proceed to surgery in UC patients is unanswered.

Additional references:

  • -Aliment Pharmacol Ther. 2008 Oct 15;28(8):966-72. Epub 2008 Jul 24.  Long-term outcome of adalimumab therapy for ulcerative colitis with intolerance or lost response to infliximab: a single-centre experience.
  • -Am J Gastroenterol (Oussalah A et al) 2010; 105: 2617-25. Multicenter study of IFX for UC
  • -Gastroenterology 2010; 138: 2282. Severe pediatric UC. 25/33 responded to IFX. colectomy rate 19% at 1 year.
  • -Gastroenterology 2009; 137: 1204 (ed), 1250. lower colectomy rates at 54wks in IFX vs placebo (+concomitant meds): 10% vs. 17%.
  • -Clin Gastro & Hep 2008; 6: 1112. Do NOT use CYA post infliximab and vice versa. n=19. 1 death due to sepsis. Remission rates occur in ~1/3rd but are of short duration.
  • -NEJM 2005; 2462. 69% clinical response @ 8 weeks (vs. 37% placebo) & 45% at week 54 (vs. 20% placebo).
  • -JPGN 2004; 38: 298. 82% short-term response, 63% sustained response; n=16.