Clarithromycin is a macrolide antibiotic commonly used to treat respiratory infections like bronchitis and pneumonia, and it is also part of the recommended triple therapy for H. pylori.
H. pylori resistance to Clarithromycin is a growing problem given that it continues to grow worldwide. In USA, based on multicenter studies, resistance rates have gone from 13-15% in 1998-2002 to 32% in 2011-20131. A 2010 study estimated that the world resistance rate was nearly 10% in 1998 and by 2009 the rate had climbed to 17%.2
H. pylori resistance often stems from a genetic mutation that allows survival in the presence of clarithromycin, as demonstrated in the figure below3.
A recent study showed that treatment failed in 61% of cultures with the 23S rRNA mutation1. Incomplete and unnecessary antibiotic regimens often allow a clarithromycin-resistant H. pylori colony to grow in place of the original gut flora. Additionally, patient’s non-compliance to proper treatment compounds the issue.
To curb the progression of the problem, many groups have begun recommending and adopting Antibiotic Stewardship Programs, including the CDC in 2014. Stewardship programs can result in significant annual drug cost savings and even larger savings when other costs are included4.
Appropriate selection of an antibiotic regimen for treatment of H. pylori prior to initiation therapy decreases the exposure to ineffective antibiotics and increases the rate of cure. In addition, in populations where H. pylori resistance exceeds 20%, antibiotic susceptibility testing can be cost-effective1.
In this study, it shows that targeted treatment increased eradication rate by 23.2% when comparing triple therapy (empiric treatment) vs susceptibility-guided therapy5.
Targeted treatment improves eradication by 23%
When treating patients for H. pylori, clarithromycin resistance testing should be conducted early. Historically, patients have been tested for resistance after moving to a third-line treatment. However, for a few reasons, this is ineffective. Failed first-line and second-line treatments can increase the likelihood of resistance5. Therefore, susceptibility testing should come before treatment.
Cost of eradication can be lowered by 17%
One study found that when compared to empiric treatment, the average cost of eradication is 17% lower in patients with targeted-based treatment6.
Potential cost of treatment failure for a patient can be around $2,000. A study looking at the economic impact of H. pylori eradication based on pre-testing for resistance found a cost saving of approximately $87–$120 compared to empiric-based therapy7. These savings come in part from a reduction in the number of doctor’s visits and the number of drugs used to treat the patient.
Table 1 below illustrates a reduction in cost per patient based on a clarithromycin susceptibility testing model. The model shows that tailored treatment yields $142 of savings per infected patient, based on using the recommended algorithm8.
References: 1. Park J, et al, Helicobacter pylori Clarithromycin Resistance and Treatment Failure are Common in the USA. Digestive Diseases and Sciences, 1-8. February 29, 2016.DOI:10.1007/s10620-016-4091-8. 2. De Francesco V, et al. Worldwide H. pylori Antibiotic Resistance: a Systematic Review, Journal of Gastrointestinal and Liver Diseases, December 2010, Vol 19, No 4, 409-414 3.Smith S, et al, Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance, World Journal of Gastroenterology, 2014;20(29):9912-9921. DOI:10.3748/wjg.v20.i29.9912. 4. Core Elements of Hospital Antibiotic Stewardship Programs. CDC. May 2016. http://www.cdc.gov/getsmart/healthcare/implementation/core-elements.html 5.Park CS, et al. Pretreatment antimicrobial susceptibility-guided vs. clarithromycin-based triple therapy for Helicobacter pylori eradication in a region with high rates of multiple drug resistance. American Journal of Gastroenterology, 2014. 109:1595-1602. 6. Cosme A, et al. Usefulness of Antimicrobial Susceptibility in the Eradication of Helicobacter pylori. Clinical Microbiology and Infection, April 2013, Vol 19, No 4. 7. Romano M, et al, Pretreatment Antimicrobial Susceptibility Testing Is Cost Saving in the Eradication of Helicobacter pylori. Clinical Gastroenterology and Hepatology. 2003;1:273-278. 8. Aamir Ali, MD. H. pylori Diagnosis, Treatment and The Challenges of Clarithromycin Resistance, Meridian Bioscience Educational Webinar Presentation. July 2016.