When people living with HIV are admitted to a hospital, they may not be able to bring their medications with them and could be prescribed new medication by a doctor who doesn't understand their complete medical history.
It's during these "transitions of care" that medication mistakes are most likely to occur. And for patients with HIV, hepatitis C (HCV) and hepatitis B (HBV), the stakes are particularly high, with medication errors leading to dangerous drug-drug interactions or the possibility of developing drug resistance.
In 2017, pharmacists working for a large Department of Veterans Affairs (VA) medical center in Dallas, Texas, decided to do something about the high rate of medication errors among these patients. They implemented an antiviral stewardship program, in which VA pharmacists worked in shifts, flagging prescriptions for HIV, HCV and HBV drugs and thoroughly reviewing those charts for possible drug-drug interactions, dosing problems or unnecessary treatments.
Prior research suggests that antiviral stewardship programs can help mitigate the challenges associated with antiretroviral treatment in hospital settings. The Texas VA program was also a success, with results summarized in a poster at the American Conference for the Treatment of HIV (ACTHIV) in Miami, Florida, in April 2019.
Among the 170 patients reviewed from January 2017 to December 2018, VA pharmacists identified 45 cases that merited follow-up phone calls with the prescribing physician. Of those 45 cases, doctors heeded the pharmacists' warning 93% of the time. Meanwhile, the program generated an estimated cost savings of $83,791.
"HIV patients are at higher risk of having potential medication errors, and this should definitely be a focus of every hospital and every hospital network," said Tomasz Jodlowski, Pharm.D., the lead author of the poster and a clinical pharmacy specialist in infectious diseases and antimicrobial stewardship at the VA North Texas Health Care System in Dallas.
"We know that transitions of care ... are times where medication errors and mistakes commonly happen," said James Cutrell, M.D., assistant professor in the department of internal medicine at University of Texas Southwestern. Considering the complexity of antiviral treatments, hospitals should consider implementing a more hands-on approach, deputizing specially trained pharmacists to proactively review patient medical charts whenever these specific medications are prescribed.
This isn't necessarily how things work today. Antiviral medications are complex, and not all hospitals have specialty pharmacists on staff. Even if they employ specialty pharmacists, most hospitals rely heavily on automated alert systems generated by electronic medical records.
Though sometimes helpful, these alerts are not sufficient to catch medication errors. Physicians subject to "alert fatigue" may not incorporate these warnings into their treatment plan, explained Cutrell. Meanwhile, as new antivirals are approved by the FDA, the electronic medical record alert systems fall out of date if drug-drug interactions are not constantly updated in the automated systems.
"Some of these programs are much more passive -- they don't actively reach out [to the prescribing clinician]," Cutrell said. "For this aspect of our program, we make an effort to reach out and communicate directly with them. That tends to increase the intervention."
Another important component of the antiviral stewardship program is the ability to trim costs for a hospital system.
"These are quite expensive medications," said Cutrell, so the cost of "errors or misprescribing can be quite substantial."
For example, some HCV medications have a wholesale price of nearly $100,000. They're usually taken for a period of 12 weeks, at which point most patients are cured. In a few cases, the antiviral stewardship program flagged instances in which a physician initiated antiviral treatment for a patient with HCV that had already been cured, potentially re-treating with an expensive and unnecessary medication.
Another example of potential cost savings is harm mitigation, explained Marcus Kouma, Pharm.D., also a clinical pharmacy specialist in infectious diseases with the VA North Texas Health Care System.
"If you avoid a drug-drug interaction, it avoids this downstream cost" of treating patients to correct the harm caused by the interaction, Kouma said.
Study authors estimated that the program generated a total cost savings of $83,791 -- a figure they derived by consulting health economics literature.
"These are rough estimates," Cutrell said. "In many ways, they're conservative."
All told, hospitals and patients are likely to benefit from stewardship programs that zero in on particularly complex medications, such as HIV antiretrovirals.
"For this particular population," said Cutrell, "I think our program of having clinical pharmacists with expert training and knowledge of these medications is a much better, more effective and efficient way to look for and to capture these medication errors."