Comedications and potential drug-drug interactions with direct-acting antivirals in hepatitis C patients on hemodialysis

Therapy as prevention toward HCV elimination in maintenance hemodialysis: a multi-center, prospective cohort study

Background

The World Health Organization has established interim guidance for hepatitis C virus (HCV) elimination. We aimed to prove the concept of "treatment as prevention" by conducting a prospective HCV elimination program for hemodialysis (HD) patients.

Methods

A universal HCV screen was launched in 22 HD centers in 2019. HCV-viremic patients were linked to care with direct-acting antivirals (DAAs). The second screen was performed in 2021 to evaluate the effect of link-to-care in lowering the prevalence of HCV viremia and the incidence of HCV new/re-infections.

Results

Of 2336 patients enrolled in the first screening in 2019, 320 (13.7%) were seropositive for anti-HCV and 181 (7.7%) were HCV-viremic. Of 152 patients successfully linked to treat with DAA, 140 (92.1%) patients achieved a sustained virological response. Of them, 1733 patients participated in the second surveillance. Five anti-HCV-negative patients experienced anti-HCV seroconversion. Of 119 DAA-cured patients and 102 spontaneous HCV clearance patients, none had HCV reinfection. The annual incidence of HCV new infection was 0.1%. Sixty-one of the 620 (9.8%) newly enrolled patients were anti-HCV-seropositive in the second survey. The overall HCV-viremic rate decreased from 7.7% in 2019 to 0.6% (15/2353) in 2021. At the institutional level, 45.5% (10/22) eradicated HCV and 82% (18/22) of HD units had no HCV new infections or reinfections.

Conclusions

The link-to-care project proved the concept of "treatment as prevention" by which HCV microelimination helps to prevent reinfection and new infections in the HD population.Trial registration: ClinicalTrials.gov identifier: NCT03803410 and NCT03891550.

TASL, TADE, and DAROC consensus for the screening and management of hepatitis C in patients with diabetes

Diabetes mellitus (DM) and hepatitis C virus (HCV) infection are prevalent diseases globally and emerging evidence demonstrates the bidirectional association between the two diseases. Direct-acting antivirals (DAAs) for HCV have a high treatment success rate and can significantly reduce the risks of short and long-term complications of HCV infection. However, despite the evidence of the association between diabetes and HCV and the benefits of anti-HCV treatment, previously published guidelines did not focus on the universal HCV screening for patients with diabetes and their subsequent management once confirmed as having HCV viremia. Nonetheless, screening for HCV among patients with diabetes will contribute to the eradication of HCV infection. Thus, the three major Taiwan medical associations of diabetes and liver diseases endorsed a total of 14 experts in the fields of gastroenterology, hepatology, diabetology, and epidemiology to convene and formulate a consensus statement on HCV screening and management among patients with diabetes. Based on recent studies and guidelines as well as from real-world clinical experiences, the Taiwan experts reached a consensus that provides a straightforward approach to HCV screening, treatment, and monitoring of patients with diabetes.

Evaluation of US Food and Drug Administration Drug Label Recommendations for Coadministration of Antivirals and Acid-Reducing Agents

Coadministration with acid-reducing agents (ARAs), including proton pump inhibitors (PPIs), histamine H2 -receptor antagonists (H2 blockers), and antacids has been demonstrated to reduce antiviral exposure and efficacy. Therefore, it is essential that US Food and Drug Administration (FDA) drug labels include recommendations to manage these drug-drug interactions (DDIs). This investigation analyzed information in FDA drug labels to manage DDIs between ARAs and antivirals approved from 1998 to 2019. To ascertain clinical adoption, we assessed whether FDA label recommendations were incorporated into current antiviral clinical practice guidelines. We identified 82 label recommendations for 43 antiviral approvals. Overall, 56.1% of recommendations were deemed clinically actionable, with the most common actionable management strategies being dose adjustment during coadministration (40.2%) and coadministration not recommended (9.8%). The sources informing DDI recommendations were clinical DDI studies (59.8%) and predictions of altered exposure (40.2%). Antivirals with low aqueous solubility were more likely to have label recommendations and were more commonly investigated using clinical DDI studies (P < 0.01). For recommendations informed by clinical DDI studies, changes in drug exposure were associated with actionable label recommendations (P < 0.01). The frequency of exposure changes in clinical DDI studies was similar across antiviral indications, but exposure changes were numerically higher for antacids (71.4%) relative to PPIs (42.9%) and H2 blockers (28.6%). Of DDI pairs identified within drug labels, 76.8% were included in guidelines, and recommended management strategies were concordant in 90.5% of cases. Our findings demonstrate that current regulatory oversight mostly (but not completely) results in actionable label recommendations to manage DDIs for high-risk antivirals.

Drug-drug interactions between direct-acting antivirals and co-medications: a territory-wide cohort study

BACKGROUND

The increasing number of direct-acting antiviral (DAA) regimens along with limited number of subjects and co-medications involved in clinical trials results in drug-drug interactions (DDIs) with DAAs is to be determined. We aimed to examine the prevalence and degree of DDIs between DAAs and other co-medications in a territory-wide cohort of chronic hepatitis C virus (HCV) patients.

METHODS

DDIs were assigned to three risk categories: Category 1-no clinically significant DDI; category 2-potential clinically significant interaction (monitoring and caution required); category 3-contraindicated (should not be co-administered).

RESULTS

Of 2981 patients (mean age 59.3 ± 12.3 years; male 60.6%), 810 (48.8%) had genotype 1 and 552 (33.2%) genotype 6 HCV among the 1661 patients with HCV genotype tested; 769 (25.8%) received sofosbuvir/velpatasvir, 510 (17.1%) sofosbuvir/ledipasvir, and 865 (29.0%) glecaprevir/pibrentasvir. More than one-fourth (26.3%) of the patients have polypharmacy (≥ 3 co-medications) in all patients, 27.0% in patients received sofosbuvir/velpatasvir, 25.1% in elbasvir/grazoprevir, and 21.2% in glecaprevir/pibrentasvir. 2037 (68.3%) patient experienced DDI (Category 2: 53.1%; Category 3: 15.2%). The commonest drugs leading to DDIs were calcium channel blockers (31.5%) and proton pump inhibitors (23.0%) in category 2; statins (10.2%), antiplatelet/anticoagulants (3.0%) and antipsychotics (2.9%) in category 3. Changing medication was the most common response from physicians in both category 2 and 3 DDIs.

CONCLUSION

The commonest co-medications leading to contraindication during DAA treatment were statins and antipsychotics. Category 2 and 3 DDIs are often managed by appropriate dose adjustments or temporary discontinuation of relevant co-medications. Careful assessment for potential DDI before DAA use is mandatory to avoid potential harmful effects.

Drug-drug interactions between antithrombotics and direct-acting antivirals in hepatitis C virus (HCV) patients: A brief, updated report

Hepatitis C virus (HCV) is one of the leading causes of chronic liver disease affecting over 71 million people worldwide. An increased incidence of atherothrombotic events [e.g. coronary artery disease (CAD), atrial fibrillation (AF)] has been observed in HCV seropositive patients. On the other hand, an increased bleeding risk is another clinical issue, particularly in subjects with liver cirrhosis, gastroesophageal varices, portal hypertension, thrombocytopenia and alcohol consumption. The introduction and progressively greater use of direct-acting antivirals (DAAs) (instead of protease and polymerase inhibitors) during the last decade has enabled a sustained virological response to be achieved in a significant percentage of patients. However, due to the high cardiovascular risk profile in HCV-infected patients, the concomitant use of antithrombotic therapies is often required, bearing in mind the possible contraindications. For example, despite better pharmacokinetic and pharmacodynamic properties compared with vitamin K-antagonists, plasma level fluctuations of direct oral anticoagulants (DOACs) due to pathological conditions (e.g. chronic kidney diseases or hepatic cirrhosis) or drug-drug interactions (DDIs) may be of great importance as regards their safety profile and overall clinical benefit. We aimed to examine and briefly summarize the significant DDIs observed between antithrombotic and HCV antiviral drugs.

Pan-genotypic direct-acting antivirals for patients with hepatitis C virus infection and chronic kidney disease stage 4 or 5

Hepatitis C virus (HCV) infection is a major health problem with significant clinical and economic burdens in patients with chronic kidney disease (CKD) stage 4 or 5. Current guidelines recommend pan-genotypic direct-acting antivirals (DAAs) to be the first-line treatment of choice for HCV. This review summarizes the updated knowledge regarding the epidemiology, natural history, public health perspectives of HCV in patients with CKD stage 4 or 5, including those on maintenance dialysis, and the performance of pan-genotypic DAAs in these patients. The prevalence and incidence of HCV are much higher in patients with CKD stage 4 or 5 than in the general population. The prognosis is compromised if HCV patients are left untreated regardless of kidney transplantation (KT). Following treatment-induced HCV eradication, patient can improve the health-related outcomes by maintaining a long-term aviremic state. The sustained virologic response (SVR₁₂) rates and safety profiles of pan-genotypic DAAs against HCV are excellent irrespective of KT. No dose adjustment of pan-genotypic DAAs is required across CKD stages. Assessing drug–drug interactions (DDIs) before HCV treatment is vital to secure on-treatment safety. The use of prophylactic or preemptive pan-genotypic DAAs in HCV-negative recipients who receive HCV-positive kidneys has shown promise in shortening KT waiting time, achieving excellent on-treatment efficacy and safety, and maintaining post-KT patient and graft survival. HCV elimination is highly feasible through multifaceted interventions, including mass screening, treatment scale-up, universal precautions, and post-SVR₁₂ reinfection surveillance.

Drug-Drug Interactions With Over-The-Counter Medicines: Mind the Unprescribed

BACKGROUND

This review provides a summary of the currently available clinical data on drug-drug interactions (DDIs) involving over-the-counter (OTC) medicines. It aims to educate and increase awareness among health care providers and to support decisions in daily practice.

METHODS

An extensive literature search was performed using bibliographic databases available through PubMed.gov. An initial structured search was performed using the keywords "drug-drug-interaction AND (over-the-counter OR OTC)," without further restrictions except for the language. The initial results were screened for all described DDIs involving OTC drugs, and further information was gathered specifically on these drugs using dedicated database searches and references found in the bibliography from the initial hits.

RESULTS

From more than 1200 initial hits (1972-June 2021), 408 relevant publications were screened for DDIs involving OTC drugs, leading to 2 major findings: first, certain types of drug regimens are more prone to DDIs or have more serious DDI-related consequences, such as antiretroviral, anti-infective, and oral anticancer therapies. Second, although most DDIs involve OTC drugs as the perpetrators, some prescription drugs (statins or phosphodiesterase-5 inhibitors) that currently have OTC status can be identified as the victims in DDIs. The following groups were identified to be frequently involved in DDIs: nonsteroidal anti-inflammatory drugs, food supplements, antacids, proton-pump inhibitors, H2 antihistamines, laxatives, antidiarrheal drugs, and herbal drugs.

CONCLUSIONS

The most significant finding was the lack of high-quality evidence for commonly acknowledged interactions. High-quality interaction studies involving different phenotypes in drug metabolism (cytochrome P450) and distribution (transporters) are urgently needed. This should include modern and critical drugs, such as oral anticancer medications and direct oral anticoagulants.

HCV GT1b-patient with alanine aminotransferase elevation and sustained virologic response achieved by grazoprevir/elbasvir discontinuation

In the present Japanese female patient with alanine aminotransferase (ALT) elevation greater than 500 IU/l during combination therapy with grazoprevir/elbasvir against HCV infection, this therapy was stopped at week 8. However, sustained virologic response was achieved. In the present report, we also focused on ALT elevation and sustained virologic response during and after antiviral therapies. The current case report demonstrates that careful monitoring of liver function tests may be required during direct-acting antiviral therapy against HCV infection because it is now possible to treat patients with polypharmacy, patients with chronic kidney disease, patients with cirrhosis or aged patients. Careful attention should be paid to liver damage as one of the adverse events in the use of HCV nonstructural protein 3/4A protease inhibitors. Of interest, many publications have addressed both ALT elevations during direct-acting antiviral therapy and viral clearance in relatively short treatment durations.