Ivacaftor-elexacaftor-tezacaftor and tacrolimus combination in cystic fibrosis

Safety and efficacy of elexacaftor/tezacaftor/ivacaftor in people with Cystic Fibrosis following liver transplantation: A systematic review

BACKGROUND & AIMS

Cystic Fibrosis (CF) liver disease progresses to liver failure requiring transplantation in about 3 % of patients, 0.7 % of CF patients are post liver transplant. The prognosis of CF has improved with the introduction of elexacaftor/tezacaftor/ivacaftor (ETI). Due to the paucity of data and concerns regarding interactions with immunosuppressive drug regimens, there is no general consensus on use of ETI post liver transplantation. The aim of this review is to report the safety and efficacy of ETI in CF patients who underwent liver transplantation.

METHODS

A systematic review was conducted through MEDLINE/Pubmed and EMBASE databases. English-written articles reporting clinical data on liver transplanted CF patients treated with ETI were included. Article quality was evaluated using the Critical Appraisal Checklist for Case Reports.

RESULTS

Twenty cases were retrieved from 6 reports. Temporary discontinuation and/or dose reduction due to elevated transaminases was required in 5 cases. ETI restarted on a reduced dose was tolerated in 3 out of 5 patients, 1 patient tolerated full dose. Tacrolimus dose change was required in 14 cases, in 1 case ETI was discontinued due to tacrolimus toxicity. Improvement in percentage predicted FEV1 was noted in 15/19 patients (median +17 %, range 8 %-38 %).

CONCLUSIONS

In the majority of liver transplanted patients ETI is well tolerated, although adverse events and liver function abnormalities may occur. Close monitoring of liver function and tacrolimus level is warranted. Significant improvement in lung function after ETI initiation is confirmed, highlighting the importance of accessing this medication for this group of patients.

Elexacaftor/tezacaftor/ivacaftor in liver or kidney transplanted people with cystic fibrosis using tacrolimus, a drug-drug interaction study

BACKGROUND

The use of elexacaftor/tezacaftor/ivacaftor (ETI) in people with cystic fibrosis (pwCF) after solid organ transplantation is controversial because of potential drug-drug interactions (DDI) with tacrolimus. We aimed to improve insight into the safety and clinical benefits of co-administration of ETI and tacrolimus in liver or kidney transplanted adult pwCF.

METHODS

In 5 pwCF, tacrolimus concentrations were monitored during 2 weeks before and 4 weeks after starting ETI treatment. Trough levels, area under the curve (AUC) and clinical effect of ETI were investigated. During the study (6 weeks in total) adverse events were monitored.

RESULTS

The DDI between tacrolimus and ETI resulted in an increased exposure of tacrolimus in all subjects, the dose adjusted AUC0-24h was 1.79 (median) times higher at the end of the study. Five dose adjustments were performed in 4 subjects in order to attain tacrolimus target range. No adverse events were reported and all subjects showed clinical improvement during ETI treatment.

CONCLUSION

The clinical value of ETI treatment in kidney and liver transplanted pwCF is clear. The use of ETI may increase tacrolimus levels moderately. Therefore, we recommend close monitoring of tacrolimus trough levels in patients who start ETI.

Drug-induced liver injury associated with elexacaftor/tezacaftor/ivacaftor: A pharmacovigilance analysis of the FDA adverse event reporting system (FAERS)

INTRODUCTION

The efficacy and safety of elexacaftor/tezacaftor/ivacaftor (ETI) have been established in prospective clinical trials. Liver function test elevations were observed in a greater proportion of patients receiving ETI compared with placebo; however, the relatively small number of patients and short duration of study preclude detection of rare but clinically significant associations with drug-induced liver injury (DILI). To address this gap, we assessed the real-world risk of DILI associated with ETI through data mining of the FDA adverse event reporting system (FAERS).

METHODS

Disproportionality analyses were conducted on FAERS data from the fourth quarter of 2019 through the third quarter of 2022. Comparative patient demographics, onset time and outcomes for ETI-DILI were also obtained.

RESULTS

452 reports of DILI associated with ETI were found, representing 2.1 % of all adverse event reports for ETI. All disproportionality measures were significant for ETI-DILI at p < 0.05; the reporting odds ratio (ROR) (2.82) was comparable to that of drugs classified by FDA as "Most-DILI concern". The most notable demographic finding was a male majority (5:4 male to female ratio) for ETI-DILI compared to a female majority (4:5 male to female ratio) for non ETI-DILI. Median ETI-DILI onset time was 50.5 days, and hospitalization was the second most common complication.

CONCLUSION

Using FAERS data, ETI was found to be disproportionately associated with DILI. Future research is needed to investigate the hepatotoxic mechanisms and assess potential mitigation strategies for ETI-induced hepatotoxicity.

Unmet challenges in cystic fibrosis treatment with modulators

INTRODUCTION

'Highly effective' modulator therapies (HEMTs) have radically changed the Cystic Fibrosis (CF) therapeutic landscape.

AREAS COVERED

A comprehensive search strategy was undertaken to assess impact of HEMT in life of pwCF, treatment challenges in specific populations such as very young children, and current knowledge gaps.

EXPERT OPINION

HEMTs are prescribed for pwCF with definite genotypes. The heterogeneity of variants complicates treatment possibilities and around 10% of pwCF worldwide remains ineligible. Genotype-specific treatments are prompting theratyping and personalized medicine strategies. Improvement in lung function and quality of life increase survival rates, shifting CF from a pediatric to an adult disease. This implies new studies addressing long-term efficacy, side effects, emergence of adult co-morbidities and possible drug-drug interactions. More sensitive and predictive biomarkers for both efficacy and toxicity are warranted. As HEMTs cross the placenta and are found in breast milk, studies addressing the potential consequences of treatment during pregnancy and breastfeeding are urgently needed. Finally, although the treatment and expected outcomes of CF have improved dramatically in high- and middle-income countries, lack of access in low-income countries to these life-changing medicines highlights inequity of care worldwide.

Use of CFTR modulators in special populations, part 3: Solid organ transplant

BACKGROUND

Solid organ transplant (SOT) recipients with cystic fibrosis (CF) may benefit from the pulmonary and extrapulmonary benefits associated with CF transmembrane conductance regulator modulators. Nevertheless, evolution of modulator safety and efficacy data prompts consideration.

METHODS

The search terms "transplant" AND "ivacaftor"(IVA) OR "lumacaftor"(LUM) OR "tezacaftor" (TEZ) OR "elexacaftor" (ELX) were utilized to conduct a scoping review of English articles from the period of January 1, 2012 to December 31, 2022. Search results from PubMed and Embase databases were reviewed by title and abstract for relevance. Included studies reported efficacy and safety outcomes of modulators in SOT recipients.

RESULTS

One hundred thirty-six patients from one cohort study (90 lung transplant recipients) and eight case reports and series (29 lung transplant recipients, 16 liver transplant recipients and one lung/liver transplant patient) were included. Post-modulator initiation, 33 patients did not necessitate tacrolimus dose adjustments, 10 required dose uptitration, and 43 required dose reductions. Moreover, LUM/IVA use with azole antifungals may lead to subtherapeutic levels but opposing effects sustained tacrolimus levels. Liver transplant recipients were more likely to experience elevations in transaminases requiring pharmacologic or medical interventions. Majority of patients experienced improvements in pulmonary function, fasting blood glucose, hemoglobin, body mass index, and rhinosinusitis symptoms. However, intolerance or lack of benefit prompted discontinuation of ELX/TEZ/IVA in over 40% of lung-transplant recipients in one study.

CONCLUSION

Modulator therapy has been reported to produce pulmonary and extra-pulmonary benefits in the CF population with SOT. Considerations for modulator therapy initiation ought to include modulator pharmacokinetics, concomitant medications, and transplant type due to the complex nature of SOT recipients.

Lung Transplantation in a New Era in the Field of Cystic Fibrosis

Lung transplantation for people with cystic fibrosis (PwCF) is a critical therapeutic option, in a disease without a cure to this day, and its overall success in this population is evident. The medical advancements in knowledge, treatment, and clinical care in the field of cystic fibrosis (CF) rapidly expanded and improved over the last several decades, starting from early pathology reports of CF organ involvement in 1938, to the identification of the CF gene in 1989. Lung transplantation for CF has been performed since 1983, and CF now accounts for about 17% of pre-transplantation diagnoses in lung transplantation recipients. Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have been the latest new therapeutic modality addressing the underlying CF protein defect with the first modulator, ivacaftor, approved in 2012. Fast forward to today, and we now have a growing CF population. More than half of PwCF are now adults, and younger patients face a better life expectancy than they ever did before. Unfortunately, CFTR modulator therapy is not effective in all patients, and efficacy varies among patients; it is not a cure, and CF remains a progressive disease that leads predominantly to respiratory failure. Lung transplantation remains a lifesaving treatment for this disease. Here, we reviewed the current knowledge of lung transplantation in PwCF, the challenges associated with its implementation, and the ongoing changes to the field as we enter a new era in the care of PwCF. Improved life expectancy in PwCF will surely influence the role of transplantation in patient care and may even lead to a change in the demographics of which people benefit most from transplantation.

Outcome of elexacaftor/tezacaftor/ivacaftor therapy in patients with cystic fibrosis and solid organ transplantation

We report a case series of four patients with cystic fibrosis (CF) and previous solid organ transplantation (SOT) receiving elexacaftor/tezacaftor/ivacaftor therapy for 6 months or more. Data was collected retrospectively. The treatment was well tolerated and all patients reported subjective improvements.

Novel Applications of Biomarkers and Personalized Medicine in Cystic Fibrosis

As routine care in cystic fibrosis (CF) becomes increasingly personalized, new opportunities to further focus care on the individual have emerged. These opportunities are increasingly filled through research in tools aiding drug selection, drug monitoring and titration, disease-relevant biomarkers, and evaluation of therapeutic benefits. Herein, we will discuss such research tools presently being translated into the clinic to improve the personalization of care in CF.

Cystic fibrosis year in review 2021

People with cystic fibrosis (CF) have an amazing outlook with the treatment availability of highly effective modulators. Unfortunately, not all people with CF are eligible for modulators leading to continued pulmonary exacerbations and advanced lung disease. Additionally, optimizing diagnosis and evaluation for CF in the newborn period continues to be an area of focus for research. This review article will work to cover articles published in 2021 with high clinical relevance related to the above topics; however, due to the extensive body of research published, this review will not be comprehensive.