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Researchers say pharmacists and physicians can work together to prescribe medications for opioid use disorder. Bisual Studio/Stocksy
  • The FDA-approved drug buprenorphine is effective in the treatment of opioid use disorder, but limited access to clinics that can prescribe this drug has contributed to only a small fraction of patients receiving the treatment.
  • Researchers have suggested that a collaborative care model involving the delegation of the care of opioid use disorder patients by clinicians to pharmacists could improve access to buprenorphine.
  • A pilot study conducted as part of a randomized phase 3 clinical trial suggests that this collaborative care model was effective in retaining a significantly higher number of patients in care after one month of treatment than standard care provided by clinicians.

A recent study suggests that 6 to 7 million individuals in the United States currently have opioid use disorder.

Buprenorphine is one of the three drugs approved by the Food and Drug Administration (FDA) for the treatment of opioid use disorder.

The benefits of buprenorphine include its low abuse potential and the ability of medical professionals to administer the drug in an outpatient setting.

Despite the effectiveness of buprenorphine in the treatment of opioid use disorder, a majority of people are unable to access the drug due to their limited access to physicians who can provide the treatment.

There is research suggesting that a collaborative care model involving the delegation of patient evaluation and a portion of treatment decisions to pharmacists by the physician is feasible and well-received by most people with opioid use disorder.

A research letter reporting results from a small pilot study conducted in Rhode Island now suggests that a greater proportion of patients continued treatment under the physician-pharmacist collaborative care model after one month than those receiving standard care from a physician.

These results suggest that this physician-pharmacist collaborative care model could expand much-needed access to buprenorphine for people with opioid use disorder.

“This study adds to previous seminal pharmacist-physician trials in the effort to expand opioid use disorder treatment,” Dr. Paolo Manneli, a psychiatrist at Duke University in North Carolina, told Medical News Today. “If the results are confirmed by larger studies, patients will be able to safely start treatment with the direct involvement of pharmacists and background supervision of prescribers. The doctor’s office would have more room to treat other and perhaps more severe patients requiring a higher level of care.”

These findings were published in the New England Journal of Medicine.

Buprenorphine is a synthetic opioid that is approved by the FDA for the treatment of opioid use disorder.

The drug activates the mu-opioid receptors that mediate the effects of heroin and morphine.

However, unlike heroin and morphine, buprenorphine only weakly activates the opioid receptor. Moreover, while heroin and morphine are short-acting opioids, buprenorphine is a long-acting drug and binds more strongly to the mu-opioid receptor.

These properties allow the use of buprenorphine as a substitute for stronger, fast-acting opioids such as heroin and morphine. Opioid replacement or substitution therapy using buprenorphine can thus help reduce cravings and withdrawal symptoms after discontinuation of the use of other opioids.

Methadone and naltrexone are other medications used for the treatment of opioid use disorder. While buprenorphine treatment can be initiated within 12 to 24 hours after the previous opioid use, naltrexone requires complete detoxification before the onset of therapy.

Methadone is also an opioid used for replacement therapy, but it’s associated with an increased risk of overdose when the dose is gradually increased during the onset of treatment. As a result, methadone is tightly regulated by federal agencies and can only be administered by specialized opioid treatment centers.

In contrast, buprenorphine can be administered in an outpatient setting by clinicians. Buprenorphine for opioid use disorder treatment is administered sublingually (under the tongue), but it has a modest potential for abuse through the intravenous route. Hence, buprenorphine is combined with naloxone, which can reduce the abuse potential of buprenorphine.

Until recently, clinicians were required to undergo extensive training and obtain a waiver to prescribe buprenorphine.

This was thought to impede the widespread acquisition of licenses for the prescription of buprenorphine by clinicians, with less than 10% of healthcare providers possessing a license to prescribe the drug.

Late last year, President Joe Biden signed a bipartisan law that eliminated the need for a license to prescribe buprenorphine. It is hoped that these changes will improve access to buprenorphine.

Before the passage of the law, almost one third of Americans lived in a county without a clinician licensed to prescribe buprenorphine. In addition, clinicians sometimes have a limited capacity to accommodate individuals with opioid use disorder due to time constraints.

To improve access to buprenorphine, physicians could potentially delegate some of the decisions regarding the treatment of individuals with opioid use disorder with this drug to pharmacists. In this physician-pharmacist collaborative care model, patients could directly attend the specialized pharmacy without an appointment.

During the first visit, the pharmacists would obtain the medical history of the patient, including the use of prescription drugs and previous use of buprenorphine, and evaluate their withdrawal symptoms. Since only a physician can prescribe buprenorphine, the pharmacist would then call the physician to determine the appropriate dosage of buprenorphine, followed by the physician providing a drug prescription.

The patients are allowed to take the medications home and initiate treatment. The patients could seek help from the pharmacist for a modification of the buprenorphine dose in case of adverse reactions or severe withdrawal symptoms from previous opioid use.

Once buprenorphine treatment is initiated, the dose is gradually increased during follow-up visits to the pharmacy until a stable dose is reached to achieve the desired suppression of cravings and to avoid illicit opioid use. During these follow-up visits, the pharmacist would again evaluate the patient and then dispense the appropriate dose of buprenorphine after examining the Prescription Drug Monitoring Program to rule out drug misuse.

Under this model, pharmacists are also required to provide counseling, patient education, track drug use, monitor for adverse effects, and regularly relay the information to the physician. This solution could be especially effective since 90% of Americans live within 5 miles of a pharmacy.

The recent pilot study compared patient retention in individuals with opioid use disorder who were receiving either usual care provided solely by the physician or collaborative care provided by the physician and pharmacist.

The study included 21 pharmacists at six specialized behavioral health pharmacies in Rhode Island. The study’s authors provided the necessary training to the pharmacists, including response to potential overdoses.

The study included 30 patients who received standard care from a clinician and another 28 who were given pharmacy-based collaborative care. The researchers found that 89% of individuals who received pharmacy-based care continued to attend the pharmacy for treatment 30 days after stabilization.

In contrast, only 17% of individuals in the standard care group persisted with attending the clinic one month after dose stabilization. The number of non-fatal overdoses and emergency department visits related to opioid use were similar in each group.

The researchers said that the greater retention of patients in the collaborative care group could be due to the convenience of receiving treatment, including eliminating the stigma of visiting the physician as well as the participants being accustomed to receiving care at the pharmacy.

A significant number of participants in this study belonged to racial/ethnic minority groups or were without permanent residence.

Researchers say these programs could especially benefit the most vulnerable populations.

“Considering overdose deaths are increasing the fastest among Black and Hispanic communities, and over 1,500 Rhode Islanders are currently unhoused, pharmacy-based addiction care models could be a pathway to promote racial and economic equity in accessing addiction treatment,” Dr. Josiah Rich, a study co-author and a professor at Brown University in Rhode Island, told Medical News Today.

“Treatment with medications can only work if it is available and accessible in the community,” he added. “Opioid use disorder is too often a lethal disease, and it kills by stigma and isolation. Widespread, equitable access to effective treatment is the answer. Our study showed that the pharmacy treatment model increases access, which benefits a diverse patient population and increases equity.”

However, large-scale studies are needed to test the feasibility of this model and further optimize this model. according to Manneli.

“Future interventions should include ways to improve the rate of treatment initiation recorded in this trial among eligible patients (just above 50%), test the feasibility and utility of conducting drug screens during induction, and clarify the best measures that must be taken to safely induce the large proportion of patients presenting at the pharmacy with synthetic opioid use (i.e., fentanyl and similar). In this ever-growing group, home induction may not be the first choice,” he said.