A pilot project in New Mexico shows that pharmacists in community practice settings can effectively manage short-course regimens for the treatment of latent tuberculosis infection (LTBI).
Thirty of 40 patients who started a weekly course of isoniazid and rifapentine therapy under the supervision of a pharmacist completed the full 12-week treatment, according to a report in the February 2020 issue of Preventing Chronic Disease.
The completion rate was similar to historic rates reported for LTBI patients treated at New Mexico Department of Health offices, according to the report.
Lead author Bernadette Jakeman, associate professor at the University of New Mexico (UNM) College of Pharmacy in Albuquerque, said pharmacists in the state have a long tradition of involvement in tuberculosis elimination efforts.
New Mexico pharmacists have been authorized since 2011 to prescribe, administer, and read tuberculin skin tests. Jakeman and her UNM colleagues have worked with health department officials to develop pharmacy-based testing programs.
“The natural next step was to look at treatment, because getting people access to both testing and treatment has been challenging,” Jakeman said.
In the recent pilot study, she said, “we were able to show that we had good completion rates with low side effects.”
The Centers for Disease Control and Prevention (CDC) estimates that about 13 million Americans are latently infected with tuberculosis. Without treatment, 5–10% of these people will progress to active tuberculosis at some point in their lifetime, according to the agency.
Jakeman said the pharmacists who participated in the pilot project “were able to encourage patients to continue with therapy that was appropriate and also help with some of the over-the-counter ... treatments for nausea [other] side effects.”
The weekly isoniazid and rifapentine regimen, also known as “3HP,” is one of three preferred LTBI treatments recommended in a new guideline from CDC and the National Tuberculosis Controllers Association.
The guideline was published in the February 14 Morbidity and Mortality Weekly Report and is the first comprehensive update to national LTBI recommendations in two decades.
Traditional LTBI treatment consisting of six or nine months of daily isoniazid therapy remains an option in the guideline but is not a preferred regimen.
In addition to 3HP, the guideline recommends rifampin monotherapy taken daily for four months or isoniazid and rifampin taken daily for three months as first-line LTBI regimens.
CDC recommended short-course treatments for LTBI well before the release of the comprehensive national guideline.
The agency in 2011 recommended the 3HP regimen as directly observed therapy with limitations on the use in children under age 12 years and people with HIV infection. In 2018, CDC recommended 3HP for adults and children ages 2–17 years, including people with HIV infection whose overall medication regimen is compatible with 3HP.
The new guideline includes those 2018 recommendations and confirms that 3HP may be self-administered or provided as directly observed therapy.
Jakeman said many patients prefer 3HP to daily short-course LTBI treatments.
“We’ve been using 3HP for years in New Mexico,” she noted. She said patients like the convenience, and pharmacists have shown that the weekly visits from the patients are manageable.
The recent pilot study was conducted in collaboration with tuberculosis program staff at the New Mexico Department of Health, with funding from the National Association of Chain Drugstores Foundation.
Pharmacists at nine sites in Albuquerque or Santa Fe, including a hospital-based pharmacy and an off-campus hospital outpatient pharmacy, underwent training to provide 3HP as directly observed therapy.
Of 102 patients with LTBI who were screened by a health department physician, 40 opted to initiate 3HP treatment at a pharmacy, which was given a prescription for the 12-dose regimen. Each weekly treatment consisted of four 900-mg tablets of rifapentine and three 900-mg tablets of isoniazid, adjusted for the patient’s weight, if necessary.
Seven of the 40 patients discontinued treatment because of potential adverse drug events, including one person who went on to complete a different LTBI regimen at a health department office. Three patients were lost to follow-up.
Twenty-six patients underwent screening but declined to receive care at a pharmacy and were instead treated at a health department office. All patients received medication at no cost regardless of where they were treated.
Jakeman said neither hospital-associated outpatient pharmacy site enrolled any patients during the 14-month study period. She attributed this to accessibility and convenience factors, such as the location and the availability of parking.
“It was really driven by patients, by where they wanted to go,” she said.
She said the biggest obstacle encountered during the project was a temporary shortage of rifapentine that necessitated a pause in enrollment.
“We ended up working together to make sure that patients that were already enrolled were able to complete treatment,” she said. Once the drug became available, the research team contacted patients who had previously been identified and offered to enroll them in the pilot study.
Jakeman encouraged other pharmacists to collaborate with their health departments on projects related to the elimination of tuberculosis.
“It’s an excellent opportunity to really provide a public health service and have an impact on your community,” she said.
[This news story will appear in an upcoming issue of AJHP.]