Imatinib‑ and ponatinib‑mediated cardiotoxicity in zebrafish embryos and H9c2 cardiomyoblasts

Tyrosine kinase inhibitors (TKIs) offer targeted therapy for cancers but can cause severe cardiotoxicities. Determining their dose‑dependent impact on cardiac function is required to optimize therapy and minimize adverse effects. The dose‑dependent cardiotoxic effects of two TKIs, imatinib and ponatinib, were assessed in vitro using H9c2 cardiomyoblasts and in vivo using zebrafish embryos. In vitro, H9c2 cardiomyocyte viability, apoptosis, size, and surface area were evaluated to assess the impact on cellular health. In vivo, zebrafish embryos were analyzed for heart rate, blood flow velocity, and morphological malformations to determine functional and structural changes. Additionally, reverse transcription‑quantitative PCR (RT‑qPCR) was employed to measure the gene expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), established markers of cardiac injury. This comprehensive approach, utilizing both in vitro and in vivo models alongside functional and molecular analyses, provides a robust assessment of the potential cardiotoxic effects. TKI exposure decreased viability and surface area in H9c2 cells in a dose‑dependent manner. Similarly, zebrafish embryos exposed to TKIs exhibited dose‑dependent heart malformation. Both TKIs upregulated ANP and BNP expression, indicating heart injury. The present study demonstrated dose‑dependent cardiotoxic effects of imatinib and ponatinib in H9c2 cells and zebrafish models. These findings emphasize the importance of tailoring TKI dosage to minimize cardiac risks while maintaining therapeutic efficacy. Future research should explore the underlying mechanisms and potential mitigation strategies of TKI‑induced cardiotoxicities.

Results of ponatinib as frontline therapy for chronic myeloid leukemia in chronic phase

BACKGROUND

Ponatinib is a third-generation BCR::ABL1 tyrosine kinase inhibitor (TKI) with robust activity in Philadelphia chromosome-positive leukemias. Herein, we report the long-term follow-up of the phase 2 trial of ponatinib in chronic myeloid leukemia in chronic phase.

METHODS

Patients received ponatinib 30 to 45 mg/day. The primary end point was the rate of 6-month complete cytogenetic response (CCyR). The study was held in June 2014 because of the risk of cardiovascular toxicity, requiring patients to change TKI.

RESULTS

Fifty-one patients were treated with ponatinib (median dose, 45 mg/day). Median age was 48 years (range, 21-75); 30 (59%) had baseline cardiovascular comorbidities. Median treatment duration was 13 months (range, 2-25). Fourteen patients (28%) discontinued ponatinib because of toxicities, 36 (71%) after the Food and Drug Administration warning/study closure, and one for noncompliance. Dasatinib was the most frequently chosen second-line TKI (n = 34; 66%). Among 46 patients evaluable at 6 months, 44 (96%) achieved CCyR, 37 (80%) major molecular response, 28 (61%) MR4, and 21 (46%) MR4.5. The cumulative 6-month rates of CCyR, major molecular response, MR4, and MR4.5 were 96%, 78%, 50%, and 36%, respectively. Durable MR4 ≥24 or ≥60 months was observed in 67% and 51% of patients, respectively. The 24-month event-free survival rate was 97%. After a median follow-up of 128 months, the 10-year overall survival rate was 90%. Eight patients (16%) had serious grade 2 to 3 cardiovascular adverse events, leading to permanent discontinuation in five (10%).

CONCLUSION

Ponatinib yielded high cytogenetic and molecular responses in newly diagnosed chronic myeloid leukemia in chronic phase. Its use in the frontline setting is hindered by arterio-/vaso-occlusive and other severe toxicities.

Toxicities associated with tyrosine kinase inhibitor maintenance following allogeneic hematopoietic cell transplantation in Philadelphia chromosome-positive acute lymphoblastic leukemia

Allogeneic hematopoietic cell transplantation (HCT) offers a potential cure in Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL); nonetheless, relapses are common and the major cause of mortality. One strategy to prevent relapse is tyrosine kinase inhibitor (TKI) maintenance post-HCT, but published clinical experience is primarily with the first-generation TKI imatinib while data with newer generation TKIs are limited. We conducted a retrospective analysis of 185 Ph+ ALL patients who underwent HCT followed by TKI maintenance from 2003 to 2021 at City of Hope. Initially, 50 (27.0%) received imatinib, 118 (63.8%) received a second-generation TKI (2G-TKI), and 17 (9.2%) received ponatinib. A total of 77 patients (41.6%) required a dose reduction of their initial TKI due to toxicity. Sixty-six patients (35.7%) did not complete maintenance due to toxicity; 69 patients (37.3%) discontinued 1 TKI, and 11 (5.9%) discontinued 2 TKIs due to toxicity. Initial imatinib versus 2G-TKI versus ponatinib maintenance was discontinued in 19 (38.0%) versus 68 (57.6%) versus 3 (17.6%) patients due to toxicity (p = .003), respectively. Patients on ponatinib as their initial TKI had a longer duration of TKI maintenance versus 2G-TKI: 576.0 days (range, 72-921) versus 254.5 days (range, 3-2740; p = .02). The most common reasons for initial TKI discontinuation include gastrointestinal (GI) intolerance (15.1%), cytopenia (8.6%), and fluid retention (3.8%). The 5-year overall survival and progression-free survival for the total population were 78% and 71%, respectively. Our findings demonstrate the challenges of delivering post-HCT TKI maintenance in a large real-world cohort as toxicities leading to TKI interruptions, discontinuation, and dose reduction were common.

Real-world outcomes of ponatinib treatment in 724 patients with CML and Ph+ ALL: a post-marketing surveillance study with a special interest in arterial occlusive events in Japan

BACKGROUND

In September 2016, ponatinib was approved in Japan for the treatment of patients with chronic myeloid leukemia with resistance/intolerance to prior tyrosine kinase inhibitors and patients with relapsed or refractory Philadelphia chromosome-positive acute lymphoblastic leukemia.

METHODS

We conducted a post-marketing all-case surveillance to study the safety and efficacy of ponatinib in clinical practice, focusing on arterial occlusive events.

RESULTS

Data from 724 patients were collected for 2 years from the initiation of ponatinib. The arterial occlusive events were reported in 6.49% (47/724) with an exposure-adjusted incidence rate of 6.8/100 person-years. The risks associated with arterial occlusive events were age and comorbidities including hypertension and diabetes. At 104 weeks, the cumulative major molecular response rate in patients with chronic-phase chronic myeloid leukemia was 67.2% and the complete cytogenetic response in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia was 80.0%. Furthermore, the estimated 1-year overall survival rate was 98.5% for chronic-phase chronic myeloid leukemia and 68.6% for Philadelphia chromosome-positive acute lymphoblastic leukemia.

CONCLUSIONS

This surveillance demonstrated that ponatinib has a favorable safety and efficacy profile in Japanese patients and also showed the necessity of closely monitoring arterial occlusive events in older adults and patients with predisposing factors for atherosclerosis.

Ponatinib-review of historical development, current status, and future research

Ponatinib is a third-generation BCR::ABL1 tyrosine kinase inhibitor (TKI) with high potency against Philadelphia chromosome (Ph)-positive leukemias, including T315I-mutated disease, which is resistant to first- and second-generation TKIs. Ponatinib was approved for T315I-mutated chronic myeloid leukemia (CML), CML resistant/intolerant to ≥2 prior TKIs, advanced phase CML and Ph-positive acute lymphoblastic leukemia (ALL) where no other TKIs are indicated, and T315I-mutated CML and Ph-positive ALL. The response-based dosing of ponatinib in chronic phase CML (CP-CML) improved treatment tolerance and reduced the risk of toxicities, including cardiovascular risks. Ponatinib-based therapy also resulted in significantly better outcomes in frontline Ph-positive ALL compared with prior TKIs and is becoming a new standard of care in this setting. As the clinical development of third-generation TKIs and their rational combinations progresses, we envision further transformative changes in the treatment of CML and Ph-positive ALL.

Levosimendan: efficacy and safety in pediatric heart failure treatment

OBJECTIVE

The objective of this study was to assess the effectiveness and safety of levosimendan as an alternative treatment for pediatric patients with decompensated heart failure unresponsive to conventional inotropes and to emphasize its role in enhancing cardiovascular stability.

METHODS

A total of 15 pediatric patients with decompensated heart failure, stemming from acute fulminant myocarditis (53.3%) and post-congenital heart disease surgery complications (46.7%), received levosimendan. The evaluation focused on adverse effects, respiratory support requirements, and concurrent inotropic medication use during levosimendan treatment. Key cardiovascular parameters were assessed at 0, 6, 12, and 24 h post-levosimendan infusion.

RESULTS

Levosimendan administration significantly improved key cardiovascular metrics. Left ventricular ejection fraction increased notably from 45±14.8% to 58±15.6% at 24 h (p<0.001). Systolic and diastolic blood pressures rose significantly, with systolic increasing from 79 (68-90) to 98 (89-109) mmHg and diastolic from 47 (40-57) to 66 (54-76) mmHg by 24 h (p<0.001). Heart rate decreased from 162 (111-175) to 132 (99-148) bpm (p=0.02), and lactate levels significantly decreased from 4.15 (2.3-6.5) to 1.85 (0.8-2.6) mmol/L within 6 h (p<0.001).

CONCLUSION

Levosimendan demonstrates its significance in managing pediatric heart failure, indicating its safety and potential to enhance cardiac outcomes by reducing reliance on traditional inotropes.

Removing the FDA's Boxed Hepatotoxicity Warning and Liver Function Testing Requirement for Ambrisentan

Importance

Endothelin receptor antagonists are first-line therapy for pulmonary arterial hypertension (PAH). The first 2 agents approved in the class, bosentan and ambrisentan, initially carried boxed warnings for hepatotoxicity and required monthly liver function tests (LFTs) as part of a risk evaluation and mitigation strategy (REMS); however, in 2011, as further safety data emerged on ambrisentan, the boxed hepatotoxicity warning and LFT requirements were removed.

Objective

To analyze changes in the use of and LFT monitoring for ambrisentan and bosentan after changes to the ambrisentan labeling and REMS.

Design, Setting, and Participants

This serial cross-sectional study used data from 3 longitudinal health care insurance claims databases-Medicaid, Optum's deidentified Clinformatics Data Mart, and Merative Marketscan-to perform an interrupted time series analysis of prescription fills and LFTs for patients taking ambrisentan and bosentan. Participants were patients filling prescriptions for ambrisentan and bosentan from July 1, 2007, to December 31, 2018. Data analysis was performed from April 2021 to August 2023.

Exposure

Removal of the boxed warning for hepatotoxicity and the REMS LFT monitoring requirements on ambrisentan in March 2011.

Main Outcomes and Measures

The primary outcomes were use of ambrisentan (ie, individuals with at least 1 dispensing per 1 000 000 individuals enrolled in the 3 datasets) vs bosentan and LFT monitoring (ie, proportion of initiators with at least 1 ordered test) before initiation and before the first refill.

Results

A total of 10 261 patients received a prescription for ambrisentan during the study period (7442 women [72.5%]; mean [SD] age, 52.6 [17.6] years), and 11 159 patients received a prescription for bosentan (7931 women [71.1%]; mean [SD] age, 47.7 [23.7] years). Removal of the ambrisentan boxed hepatotoxicity warning and LFT monitoring requirement was associated with an immediate increase in the use of ambrisentan (1.50 patients per million enrollees; 95% CI, 1.08 to 1.92 patients per million enrollees) but no significant change in the use of bosentan. There were reductions in recorded LFTs before drug initiation (13.1% absolute decrease; 95% CI, -18.2% to -8.0%) and before the first refill (26.4% absolute decrease; 95% CI, -34.4% to -18.5%) of ambrisentan but not bosentan.

Conclusions and Relevance

In this serial cross-sectional study of ambrisentan, labeling changes and removal of the REMS-related LFT requirement were associated with shifts in prescribing and testing behavior for ambrisentan but not bosentan. Further clinician education may be needed to maximize the benefits of REMS programs and labeling warnings designed to ensure the safe administration of high-risk medications.

Ponatinib vs Imatinib in Frontline Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: A Randomized Clinical Trial

Importance

In newly diagnosed Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL), disease progression due to acquired resistance to first- or second-generation BCR::ABL1 tyrosine kinase inhibitors is common. Ponatinib inhibits BCR::ABL1 and all single-mutation variants, including T315I.

Objective

To compare frontline ponatinib vs imatinib in adults with newly diagnosed Ph+ ALL.

Design, Setting, and Participants

Global registrational, phase 3, open-label trial in adults aged 18 years or older with newly diagnosed Ph+ ALL. From January 2019 to May 2022, eligible patients at 77 sites were randomized 2:1 to ponatinib (30 mg/d) or imatinib (600 mg/d) with reduced-intensity chemotherapy, followed by single-agent ponatinib or imatinib after the cycle 20 phase of the trial. The last date of follow-up for this analysis was August 12, 2022.

Intervention

Patients received ponatinib, 30 mg/d, or imatinib, 600 mg/d, with reduced-intensity chemotherapy, followed by single-agent ponatinib or imatinib after cycle 20. The ponatinib dose was reduced to 15 mg on achievement of minimal residual disease-(MRD) negative complete remission.

Main Outcomes and Measures

The primary end point of this interim analysis was MRD-negative complete remission (≤0.01% BCR::ABL1 [MR4] centrally assessed by reverse transcriptase-quantitative polymerase chain reaction), with complete remission maintained for at least 4 weeks at the end of cycle 3. The key secondary end point was event-free survival.

Results

Of 245 patients randomized (median age, 54 years; 133 [54.3%] female), 232 (ponatinib, n = 154; imatinib, n = 78) who had p190 or p210 dominant isoforms verified by the central laboratory were analyzed for the primary end point. The MRD-negative complete remission rate (primary end point) was significantly higher with ponatinib (34.4% [53/154]) vs imatinib (16.7% [13/78]) (risk difference, 0.18 [95% CI, 0.06-0.29]; P = .002). At the data cutoff, event-free survival had not met the prespecified number of events. Median event-free survival was not reached in the ponatinib group and was 29 months in the imatinib group. The most common adverse events were similar between treatment groups. Arterial occlusive events were infrequent and comparable between groups (ponatinib, 2.5%; imatinib, 1.2%).

Conclusions and Relevance

Ponatinib demonstrated a superior rate of MRD-negative complete remission at the end of induction vs imatinib when combined with reduced-intensity chemotherapy in adults with newly diagnosed Ph+ ALL. The safety profile of ponatinib was comparable with imatinib.

Trial Registration

ClinicalTrials.gov Identifier: NCT03589326.

Long-term safety and tolerability of ambrisentan treatment for pediatric patients with pulmonary arterial hypertension: An open-label extension study

This open-label, extension study assessed long-term safety, tolerability, and efficacy of ambrisentan in a pediatric population (age 8- < 18 years) with pulmonary arterial hypertension (PAH). Following completion of a 6-month, randomized study, participants entered the long-term extension at individualized ambrisentan dosages (2.5/5/7.5 or 10 mg/day). Safety assessments included adverse events (AEs), AEs of special interest, and serious AEs (SAEs); efficacy outcomes included 6-min walking distance (6MWD) and World Health Organization functional class (WHO FC). Thirty-eight of 41 (93%) randomized study participants entered the extension; 21 (55%) completed (reaching age 18 years). Most participants received concomitant phosphodiesterase-5 inhibitors (n = 25/38, 66%). Median ambrisentan exposure was 3.5 years. Most participants experienced ≥ 1 AE (n = 34/38, 89%), and 21 (55%) experienced SAEs, most commonly worsening PAH (n = 3/38, 8%), acute cardiac failure, pneumonia, or anemia (n = 2/38; 5% each); none considered ambrisentan-related. Seven participants (18%) died, with recorded reasons (MedDRA preferred term): cardiac failure (n = 2), PAH (n = 2), COVID-19 (n = 1), acute right ventricular failure (n = 1), and failure to thrive (n = 1); median time to death: 5.2 years. Anemia and hepatotoxicity AEs were generally mild to moderate and did not require ambrisentan dose adjustment. Assessed at study end in 29 participants (76%), mean 6MWD improved by 17% (standard deviation: 34.3%), and all (29/29, 100%) had improved or unchanged WHO FC.    Conclusion: Long-term weight-based ambrisentan dosing, alone or combined with other PAH therapies in children with PAH aged 8- < 18 years, exhibited tolerability and clinical improvements consistent with prior randomized study results.    Trial registration: NCT01342952, April 27, 2011. What is Known: • The endothelin receptor antagonist, ambrisentan, is indicated for treatment of pulmonary arterial hypertension (PAH). Previous studies have shown similar efficacy and tolerability in pediatric patients as in adults. What is New: • This open-label extension study assessed the long-term use of ambrisentan in pediatric patients (8-<18 years) with PAH, most of whom were also receiving recommended background PAH treatment. • Weight-based dosing of ambrisentan, given alone or in combination with other PAH therapies, was well tolerated with clinical improvements consistent with prior randomized study results.

Resmetirom (Rezdiffra) for metabolic dysfunction-associated steatohepatitis

Resmetirom (Rezdiffra – Madrigal), a thyroid hormone receptor-beta agonist, has received accelerated approval from the FDA for treatment of noncirrhotic nonalcoholic steatohepatitis (NASH) with moderate to advanced fibrosis in adults.

Absence of cross-toxicity between MET inhibitors in a non-small-cell lung cancer with a MET exon 14 skipping mutation

INTRODUCTION

Selective tyrosine kinase inhibitors are proven effective in patients with non-small lung cancer (NSCLC) with a MET exon 14 skipping mutation.

CASE PRESENTATION

The patient developed a metastatic lung adenocarcinoma with a MET exon 14 skipping mutation. She was treated with a first 1b MET inhibitor, Capmatinib, but had to stop the drug because of major hepatotoxicity. A few months later, she started Tepotinib, another 1b MET inhibitor with this time, no sign of hepatotoxicity.

DISCUSSION

Adverse events are frequent with 1b MET inhibitors. However, there is a wide interpatient variability. Absence of cross-toxicity between Capmatinib and Tepotinib is misunderstood but can be explained by slight differences in phamarcodynamics and pharmacokinetics. Practitionners have to be warned about severe adverse events to stop or change the drug if necessary.

CONCLUSION

This is the first case showing the absence of cross-toxicity between 1b MET inhibitors.

Long-Term Follow-Up in Patients With Chronic Myeloid Leukemia Treated With Ponatinib in a Real-World Cohort: Safety and Efficacy Analysis

BACKGROUND

Ponatinib is a third-generation tyrosine-kinase inhibitor (TKI), indicated in patients with chronic phase (CP), accelerated phase (AP), or blast phase (BP) chronic myeloid leukemia (CML), who are resistant or intolerant to ≥2 prior TKIs, patients for whom subsequent treatment with imatinib is not appropriate, and patients who have a T315I mutation.

PATIENTS AND METHODS

We aimed to evaluate outcomes of ponatinib treatment, including safety, with focus on cardiovascular toxicity, in real-world patients from Argentina. Data from patients with CP CML treated with ponatinib was retrospectively retrieved from 2013 to 2023 in 7 centers.

RESULTS

Seventy-two patients were included (median age: 44 years; male: 55.5%; T315I mutation: 32%: median treatment duration: 36 months. At baseline, 57 patients (79%) had a breakpoint cluster region-Abelson (BCR::ABL1) transcript level >10% on the international reporting scale (BCR::ABL1 IS). A molecular response (MR, BCR::ABL1 (IS) <1%) was achieved at 12 months in 51.6% of evaluable patients; 57% maintained MR at last follow-up. Overall, 43% and 25% maintained major MR (MMR) or deep MR (DMR) (MR4.0-MR5.0), respectively at last follow-up. Twelve (16.6%) ponatinib-resistant patients were rescued with allogeneic hematopoietic stem cell transplantation. The estimated 2-year progression-free survival (PFS) was 84%. Ponatinib dose was reduced during treatment in 22 patients; nevertheless, MMR was maintained in 50% of these patients. Severe arterial occlusive events (AOE) were reported in 10.9% of patients after a median treatment of 5 months.

CONCLUSION

CV toxicity was consistent with clinical trials and other real-world registries. Older age, hypercholesterolemia and a SCORE risk >2% were significantly associated with higher risk of AOEs. Controlling CV risk factors and reducing doses at optimal time points may help to optimize ponatinib use in daily practice.

Safety of Levosimendan in Pediatric Patients: An Up-to-Date Systematic Review

BACKGROUND

The potential risks associated with the use of levosimendan in the pediatric population has not been systematically evaluated. This study aimed to review the available evidence regarding the safety of this treatment.

METHODS

Bio Med Central, PubMed, Embase, and the Cochrane Central Register of clinical trials were searched for studies describing levosimendan administration in the pediatric population in any setting. Relevant studies were independently screened, selected, and their data extracted by two investigators. The authors excluded: reviews, meta-analyses, as well as basic research and trials involving patients >18 years old. The primary outcome was the number and the type of adverse side effects reported during levosimendan administration.

RESULTS

The updated systematic review included 48 studies, enrolling a total of 1,271 pediatric patients who received levosimendan as treatment (790 patients in the 11 studies that reported side effects). The primary adverse effects of levosimendan administration were hypotension and cardiac arrhythmias, particularly tachycardia. Hypotension occurred in approximately 28.9% of patients, while arrhythmia occurred in about 12.3% of patients. Meta analysis of RCTs revealed a rate of all-cause mortality of 2.0% (8 out of 385) in the levosimendan group compared to 3.9% (15 out of 378) in the control group (dobutamine, milrinone or placebo) (risk ratio [RR] = 0.55; 95% confidence interval [CI] = 0.25-1.21; P = 0.14; I2 = 0%) CONCLUSIONS: Hypotension and cardiac arrhythmia are the most reported side effects of levosimendan in pediatric patients. However, adverse events remain underreported, especially in randomized trials.

Repeated Levosimendan Infusions in the Management of Advanced Heart Failure: Review of the Evidence and Meta-analysis of the Effect on Mortality

ABSTRACT

In the latest years, several studies described the impact of repetitive/intermittent i.v. levosimendan treatment in the management of advanced heart failure. For this updated review, we systematically searched the literature for clinical trials, registries , and real-world data and identified 31 studies that we commented in a narrative review: 3814 patients were described, of whom 1744 were treated repetitively with levosimendan. On the basis of the nature of the study protocols and of the end points, out of those studies, we further selected 9 that had characteristics, making them suitable for a meta-analysis on mortality. This short list describes data from 680 patients (of whom 399 received repeated doses of levosimendan) and 110 death events (of which 50 occurred in the levosimendan cohort). In the meta-analysis, repetitive/intermittent therapy with i.v. levosimendan was associated with a significant reduction in mortality at the longest time point available: 50 of 399 (12.5%) versus 60 of 281 (21.4%) in the control arms, with a risk ratio of 0.62 (95% confidence interval, 0.42-0.90; P < 0.01). In a sensitivity analysis, removing each trial and reanalyzing the remaining data set did not change the trend, magnitude, or significance of the results. A visual inspection of the funnel plot did not suggest publication bias. The results provide a very strong rationale for continuing to investigate the repetitive use of levosimendan in patients with advanced heart failure by properly powered regulatory clinical trials. Meanwhile, it seems that the use of repetitive/intermittent i.v. levosimendan infusions has become one of the few effective options for preserving the hemodynamic and symptomatic balance in such patients.

Bosentan and ambrisentan in the treatment of idiopathic pulmonary fibrosis: a meta-analysis

OBJECTIVE

The aim is to showcase the effectiveness and safety of bosentan or ambrisentan in individuals diagnosed with idiopathic pulmonary fibrosis (IPF) and offer fresh evidence for the management of this condition.

MATERIALS AND METHODS

For this research, we conducted a meta-analysis of randomized controlled trials by searching various databases, including the Cochrane Library, Excerpta Medica Database, PubMed, and Web of Science. The retrieval was conducted until November 2021. We analyzed the variances in 6-minute walk distance (6MWD), death, diffusion capacity for carbon monoxide (DLCO), forced vital capacity (FVC), hospitalization, IPF worsening, mean pulmonary arterial pressure, serious adverse events (SAEs), Short Form-36 improved, and St. George's Respiratory Questionnaire between the treatment and control groups.

RESULTS

A sum of six studies involving 1,928 participants were found to meet the inclusion criteria. The quality of evidence was high. The control group had significantly higher values for 6MWD, DLCO, and FVC compared to the ambrisentan treatment group. The rates of hospitalization and IPF worsening were considerably greater in comparison with the control group. The bosentan group exhibited significantly reduced rates of hospitalization and IPF worsening in comparison with the control group. Both drugs did not cause any raising in death or SAEs when in comparison with the control group.

CONCLUSIONS

The findings of this research validate the effectiveness and safety of bosentan for treating IPF patients. This medication can enhance the quality of life for individuals with IPF without causing any significant increase in SAEs. However, it does not have a notable influence on the long-term prognosis. The findings of this research do not endorse the utilization of ambrisentan in individuals diagnosed with IPF.

Comparative efficacy and safety of different doses of ponatinib versus other tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia: a systematic review and network meta-analysis

OBJECTIVE

Ponatinib was recommended with caution because of its high risk of causing arterial occlusion events in chronic myeloid leukemia (CML) patients. The purpose of this study was to understand the efficacy and safety of different doses of ponatinib in the treatment of CML, and to compare it with other tyrosine kinase inhibitors (TKIs).

METHOD

A network meta-analysis (NMA) was conducted by searching randomized controlled trials (RCTs) of ponatinib in patients with CML to compare the efficacy and safety of ponatinib, and ranked under the cumulative ranking curve (SUCRA) to evaluate the optimal treatment.

RESULTS

A total of seven articles with eight RCTs were included in this study, involving 45 mg, 30 mg and 15 mg ponatinib doses. Seven outcome indexes were analyzed. The results showed that 45 mg ponatinib was superior to other doses of ponatinib and other TKIs in CCyR, MCyR and CHR, but the incidence of SAEs and AOEs was significantly higher than other treatment regimens.

CONCLUSION

Ponatinib, with an initial dosage of 45 mg and a gradual reduction to 15 mg, may be a more favorable option for patients with CML at all stages of disease progression, rather than just those in the chronic phase of CML.

Ponatinib-Related Vasospastic Angina

Tyrosine kinase inhibitors (TKIs) are essential drugs for chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. Cardiovascular or arteriothrombotic adverse events have been reported in patients treated with TKIs. We report 3 cases of Ponatinib-related vasospastic angina, in which prophylactic administration of nitrates or calcium channel blockers was effective.

Addendum to the German Consensus Recommendations on Ponatinib in the Treatment of Chronic Myeloid Leukemia

BACKGROUND

Based on the new data from the primary analysis of the OPTIC (Optimizing Ponatinib Treatment in CP-CML) trial on dose optimization of ponatinib in patients with chronic phase (CP)-CML, the German consensus paper on ponatinib published in 2020 (Saussele S et al., Acta Haematol. 2020) has been updated in this addendum.

SUMMARY

Focus is on the update of efficacy and safety of ponatinib, reflecting the new data set, as well as the update of the benefit-risk assessment and recommendations for ponatinib starting dose in CP-CML - provided that the decision to use ponatinib has already been made. Furthermore, based on OPTIC and additional empirical data, the expert panel collaborated to develop a decision tree for ponatinib dosing, specifically for intolerant and resistant patients. The recommendations on cardiovascular management have also been updated based on the most recent 2021 guidelines of the European Society of Cardiology (ESC) on cardiovascular disease prevention in clinical practice.

KEY MESSAGES

The OPTIC data confirm the high efficacy of ponatinib in patients with CP-CML and provide the basis for individualized dose adjustment during the course of treatment.

Focal Segmental Sclerosis Associated with the Novel Multi-tyrosine Kinase Inhibitor Ponatinib

Ponatinib is a novel multi-tyrosine kinase inhibitor (TKI) with potent inhibitory activity against refractory chronic myeloid leukemia (CML). Despite its high clinical efficacy, ponatinib induces various adverse events due to its multi-target characteristic. However, renal complications associated with ponatinib are rare. A 76-year-old woman had a history of chronic myeloid leukemia (CML) resistant to imatinib and nilotinib. Our patient developed proteinuria and renal function deterioration during treatment with ponatinib but not with imatinib or nilotinib. We herein report the first case of a patient with secondary focal segmental glomerulosclerosis (FSGS) with partial glomerular collapse induced by ponatinib treatment.

Dose optimisation of ponatinib in chronic phase chronic myeloid leukemia

INTRODUCTION

Ponatinib exhibits a high inhibition potency on wild-type and most mutated forms of the BCR:ABL1 kinase, but also a significant cardiovascular toxicity. Improving the efficacy/safety ratio should allow patients to safely draw benefit from the drug.

AREAS COVERED

Based on pharmacological findings and international guidelines on chronic myeloid leukemia and cardiovascular risk management, as well as on the most recent data collected in real-life studies and in a randomized phase II trial, we propose a decision-tree of dose selection of the drug.

EXPERT OPINION

We distinguish (1) highly resistant patients according to poor previous response to second generation tyrosine kinase inhibitors (complete hematologic response or less) or to mutational status (T315I, E255V, alone or within compound mutations), requiring a starting daily dose of 45 mg, reduced to 15 or 30 mg according to the patient's profile, preferentially upon major molecular achievement (3-log reduction or MR3, BCR:ABL1 ≤ 0.1%IS); (2) less-resistant patients justifying an initial dose of 30 mg, reduced to 15 mg upon MR2 (BCR:ABL1 ≤ 1%IS) or preferentially MR3 in patients with a favorable safety profile; (3) intolerant patients to be treated by 15 mg.

Ponatinib after failure of second-generation tyrosine kinase inhibitor in resistant chronic-phase chronic myeloid leukemia

Ponatinib, the only third-generation pan-BCR::ABL1 inhibitor with activity against all known BCR::ABL1 mutations including T315I, has demonstrated deep and durable responses in patients with chronic-phase chronic myeloid leukemia (CP-CML) resistant to prior second-generation (2G) TKI treatment. We present efficacy and safety outcomes from the Ponatinib Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) and CML Evaluation (PACE) and Optimizing Ponatinib Treatment in CP-CML (OPTIC) trials for this patient population. PACE (NCT01207440) evaluated ponatinib 45 mg/day in CML patients with resistance to prior TKI or T315I. In OPTIC (NCT02467270), patients with CP-CML and resistance to ≥2 prior TKIs or T315I receiving 45 or 30 mg/day reduced their doses to 15 mg/day upon achieving ≤1% BCR::ABL1^IS or received 15 mg/day continuously. Efficacy and safety outcomes from patients with CP-CML treated with ≥1 2G TKI (PACE, n = 257) and OPTIC (n = 93), 45-mg starting dose cohort, were analyzed for BCR::ABL1^IS response rates, overall survival (OS), progression-free survival (PFS), and safety. By 24 months, the percentages of patients with ≤1% BCR::ABL1^IS response, PFS, and OS were 46%, 68%, and 85%, respectively, in PACE and 57%, 80%, and 91%, respectively, in OPTIC. Serious treatment-emergent adverse events and serious treatment-emergent arterial occlusive event rates were 63% and 18% in PACE and 34% and 4% in OPTIC. Ponatinib shows high response rates and robust survival outcomes in patients whose disease failed prior to 2G TKIs, including patients with T315I mutation. The response-based dosing in OPTIC led to improved safety and similar efficacy outcomes compared with PACE.

Ponatinib with fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor chemotherapy for patients with blast-phase chronic myeloid leukaemia (MATCHPOINT): a single-arm, multicentre, phase 1/2 trial

BACKGROUND

Outcomes for patients with blast-phase chronic myeloid leukaemia are poor. Long-term survival depends on reaching a second chronic phase, followed by allogeneic haematopoietic stem-cell transplantation (HSCT). We investigated whether the novel combination of the tyrosine-kinase inhibitor ponatinib with fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin (FLAG-IDA) could improve response and optimise allogeneic HSCT outcomes in patients with blast-phase chronic myeloid leukaemia. The aim was to identify a dose of ponatinib, which combined with FLAG-IDA, showed clinically meaningful activity and tolerability.

METHODS

MATCHPOINT was a seamless, phase 1/2, multicentre trial done in eight UK Trials Acceleration Programme-funded centres. Eligible participants were adults (aged ≥16 years) with Philadelphia chromosome-positive or BCR-ABL1-positive blast-phase chronic myeloid leukaemia, suitable for intensive chemotherapy. Participants received up to two cycles of ponatinib with FLAG-IDA. Experimental doses of oral ponatinib (given from day 1 to day 28 of FLAG-IDA) were between 15 mg alternate days and 45 mg once daily and the starting dose was 30 mg once daily. Intravenous fludarabine (30 mg/m2 for 5 days), cytarabine (2 g/m2 for 5 days), and idarubicin (8 mg/m2 for 3 days), and subcutaneous granulocyte colony-stimulating factor (if used), were delivered according to local protocols. We used an innovative EffTox design to investigate the activity and tolerability of ponatinib-FLAG-IDA; the primary endpoints were the optimal ponatinib dose meeting prespecified thresholds of activity (inducement of second chronic phase defined as either haematological or minor cytogenetic response) and tolerability (dose-limiting toxicties). Analyses were planned on an intention-to-treat basis. MATCHPOINT was registered as an International Standard Randomised Controlled Trial, ISRCTN98986889, and has completed recruitment; the final results are presented.

FINDINGS

Between March 19, 2015, and April 26, 2018, 17 patients (12 men, five women) were recruited, 16 of whom were evaluable for the coprimary outcomes. Median follow-up was 41 months (IQR 36-48). The EffTox model simultaneously considered clinical responses and dose-limiting toxicities, and determined the optimal ponatinib dose as 30 mg daily, combined with FLAG-IDA. 11 (69%) of 16 patients were in the second chronic phase after one cycle of treatment. Four (25%) patients had a dose-limiting toxicity (comprising cardiomyopathy and grade 4 increased alanine aminotransferase, cerebral venous sinus thrombosis, grade 3 increased amylase, and grade 4 increased alanine aminotransferase), fulfilling the criteria for clinically relevant activity and toxicity. 12 (71%) of 17 patients proceeded to allogeneic HSCT. The most common grade 3-4 non-haematological adverse events were lung infection (n=4 [24%]), fever (n=3 [18%]), and hypocalcaemia (n=3 [18%]). There were 12 serious adverse events in 11 (65%) patients. Three (18%) patients died due to treatment-related events (due to cardiomyopathy, pulmonary haemorrhage, and bone marrow aplasia).

INTERPRETATION

Ponatinib-FLAG-IDA can induce second chronic phase in patients with blast-phase chronic myeloid leukaemia, representing an active salvage therapy to bridge to allogeneic HSCT. The number of treatment-related deaths is not in excess of what would be expected in this very high-risk group of patients receiving intensive chemotherapy. The efficient EffTox method is a model for investigating novel therapies in ultra-orphan cancers.

FUNDING

Blood Cancer UK and Incyte.