Prognostic significance of 8 weeks' relative dose intensity of lenvatinib in treatment of radioiodine-refractory differentiated thyroid cancer patients

Lenvatinib rechallenge after failure of lenvatinib and sorafenib in metastatic thyroid cancer

The oral multikinase inhibitors sorafenib and lenvatinib are currently available as first-line treatment for patients with unresectable or metastatic thyroid cancer. However, treatment options for patients who are refractory to these multikinase inhibitors are limited. This study aimed to evaluate the safety and efficacy of rechallenged lenvatinib after failure of both lenvatinib and sorafenib in patients with metastatic thyroid cancer in the real-world clinical practice. We retrospectively reviewed the data of consecutive 16 patients with metastatic thyroid cancer who received lenvatinib as a rechallenge after failure of initial lenvatinib and sorafenib treatment at Shizuoka Cancer Center between 2016 and 2023. Of these, the initial lenvatinib was discontinued in 12 patients owing to progressive disease, in 3 patients owing to adverse events, and in 1 patient owing to both. The overall response rate was 6.7%, and disease control was achieved by rechallenge with lenvatinib in all patients with the target lesions. The median progression free survival after rechallenging with lenvatinib was 15.0 months. No new signs of toxicity were observed after rechallenging with lenvatinib. Our findings suggest that rechallenge with lenvatinib after failure of both lenvatinib and sorafenib showed manageable safety and modest efficacy in patients with metastatic thyroid cancer in clinical practice. The strategy of lenvatinib rechallenge may provide an alternative option for patients with no targetable driver genes or when selective kinase inhibitors are not indicated.

Long-term follow-up and exploratory analysis of lenvatinib in patients with metastatic or recurrent thymic carcinoma: Results from the multicenter, phase 2 REMORA trial

OBJECTIVES

The main objective of this report was to detail the long-term follow-up data from the REMORA study, which investigated the safety and efficacy of lenvatinib in patients with thymic carcinoma. In addition, an exploratory analysis of the association between relative dose intensity (RDI) and the efficacy of lenvatinib is presented.

MATERIALS AND METHODS

The single-arm, open-label, phase 2 REMORA study was conducted at eight Japanese institutions. Forty-two patients received oral lenvatinib 24 mg once daily in 4-week cycles until the occurrence of intolerable adverse events or disease progression. The REMORA long-term follow-up data were evaluated, including overall survival (OS). RDI was calculated by dividing the actual dose administered to the patient by the standard recommended dose. This trial is registered on JMACCT (JMA-IIA00285) and on UMIN-CTR (UMIN000026777).

RESULTS

The updated median OS was 28.3 months (95 % confidence interval [CI]: 17.1-34.0 months), and the OS rate at 36 months was 35.7 % (95 % CI: 21.7 %-49.9 %). When grouped by RDI of lenvatinib, the median OS was 38.5 months (95 % CI: 31.2-not estimable) in patients with ≥ 75 % RDI and 17.3 months (95 % CI: 13.4-26.2 months) in patients with < 75 % RDI (hazard ratio 0.46 [95 % CI: 0.22-0.98]; P = 0.0406) at 8 weeks. Patients who maintained their lenvatinib dose over 8 weeks had a higher objective response rate than patients whose doses were reduced (75.0 % vs 29.4 %; P = 0.0379). No new safety concerns or treatment-related deaths were reported, and lenvatinib had a tolerable safety profile.

CONCLUSION

This follow-up report updated OS in patients with metastatic or recurrent thymic carcinoma. A higher RDI of lenvatinib at 8 weeks could be associated with improved outcomes.

Utility and optimal management of planned drug holidays during lenvatinib treatment in patients with unresectable differentiated thyroid cancer: a real-world multi-center study

PURPOSE

Lenvatinib achieves favorable therapeutic outcomes for patients with radioactive iodine therapy refractory differentiated thyroid cancer (DTC); however, its use is associated with a high incidence of adverse events. To avoid severe adverse events, planned drug holidays (PDH) have been proposed. This study aimed to evaluate treatment effects, identify prognostic factors, and investigate the usefulness of PDH in patients with unresectable DTC who received lenvatinib across the multi-institutions.

METHODS

Fifty-one patients with unresectable DTC treated with lenvatinib were evaluated retrospectively. Overall survival (OS) and progression-free survival (PFS) were calculated, and prognostic factors were assessed. OS, PFS, and time to treatment failure (TTF) were compared between patients with and without PDH. Lenvatinib administration schedule was evaluated in PDH.

RESULTS

The 3-year OS and PFS rate were 53.5% and 42.1%, respectively. Multivariate analysis revealed that presence of maximum size of lung metastasis ≥10 mm was independent prognostic factor for poorer OS and PFS, and histology other than papillary thyroid carcinoma was the independent prognostic factor for poorer PFS. Twenty-five patients (49%) treated with PDH. There were significant differences in OS, PFS, and TTF between patients with and without PDH. Various schedules were used in PDH. Eight (32%) patients required switch to the different administration schedule.

CONCLUSION

Our results suggest that PDHs may extend OS, PFS, and TTF. In patients with PDH, various schedules used for lenvatinib administration highlight the difficulty in determining a uniform administration schedule. Therefore, it is crucial to consider the optimal lenvatinib administration schedule on a case-by-case basis.

The importance of early-stage blood pressure control in thyroid cancer patients treated with lenvatinib from the perspective of dose intensity

PURPOSE

Lenvatinib (LEN) is a multikinase inhibitor that strongly inhibits tyrosine kinase receptors, especially VEGFR-2, which can cause hypertension, as well as strong tumor shrinkage. Though control of any side effects (SEs) is important for maintaining dose intensity (DI), hypertension is particularly important, because blood pressure (BP) can change quickly and respond to LEN administration and withdrawal, and it can be controlled with antihypertensive medications. Focusing on the early phase of treatment, the effect of BP 8 weeks after LEN initiation (BP8w) on DI at 8 weeks (DI8w) was investigated.

METHODS

The subjects were 85 thyroid cancer patients who started LEN at 24 mg/day and continued for ≥8 weeks. The BP at the start of LEN (BPbase), BP8w grade, and DI8w were examined.

RESULTS

Median (range) systolic BP changed significantly from BPbase of 117 (84-167) mmHg to BP8w of 134 (103-168) mmHg (p<0.001). Antihypertensive treatment at baseline, systolic BPbase, and male sex were related to higher DI8w on multivariate analysis. The median DI8w of the 23 patients who required dose modification due to hypertension was 20.2 mg/day (n=6) in grade 1, 15.8 mg/day (n=13) in grade 2, and 14.5 mg/day (n=4) in grade 3, showing a trend toward lower DI8w as the grade level increased.

CONCLUSION

LEN can increase BP by 20 mmHg at 8 weeks even with intensive antihypertensive management. Baseline antihypertensive treatment and BPbase can affect DI8w. A higher DI8w may be achieved by aiming for a low 8-week BP with more intensive antihypertensive therapy after LEN initiation.

Sustained antitumor response to lenvatinib with weekend-off and alternate-day administration in chemotherapy-refractory thymic carcinoma: a case report

Lenvatinib is a multitargeted kinase inhibitor and maintaining its dose intensity has been shown to be beneficial in patients with thyroid and hepatocellular carcinomas. However, most patients require lenvatinib interruption and dose reduction due to the high incidence of adverse events (AEs). Lenvatinib was recently approved in Japan for patients with unresectable thymic carcinoma; however, real-world evidence of its clinical benefit is limited. Here, we report the case of chemotherapy-refractory thymic carcinoma in a patient who was administered a starting dose of lenvatinib using a 5-day on/2-day off (weekend-off) protocol, followed by alternate-day administration after fatigue onset derived from overt or subclinical hypothyroidism. Consequently, the patient exhibited a durable response to lenvatinib, with a 17-month progression-free survival without any severe or intolerable AEs. The present case suggests that maintaining lenvatinib dose intensity using such alternative administration regimens contributes to favorable clinical outcomes in thymic carcinoma.

Successful dose escalation of lenvatinib for thyroid cancer after disease progression

PURPOSE

Lenvatinib is started at a standard dose, continuing with dose reduction and interruption, balancing between efficacy and adverse events (AEs). Because few drugs are available for thyroid cancer, efforts for continuing treatment with one agent, such as "dose escalation (DE)", are made. The dose is increased, aiming to regain the anti-tumor effect after dose reduction. The effects of lenvatinib DE in differentiated thyroid carcinoma (DTC) patients are reported.

PATIENTS AND METHODS

The efficacy of lenvatinib DE in DTC patients using the serum thyroglobulin (Tg) level and management of AEs was investigated.

RESULTS

A total of 70 DE episodes in 33 patients were investigated. The median increased dose was 2.0 (1.0-14.0) mg, increased from 8.6 (2-16) mg to 10.1 (6-24) mg. The serum Tg level decreased in 53 DE episodes. Though the serum Tg level in 17 DE episodes was not decreased, the Tg rate of increase was decreased in 7 of these DE episodes using the Tg-doubling rate. Overall, clinical benefit was seen in 60 (86%) DE episodes. AEs that could not be controlled after DEs were seen in only 16% of cases. No intolerable AEs were observed in patients who received more drug holidays at the time of DEs compared to two times before the DEs.

CONCLUSION

DE may become one of the standard treatment strategies after disease progression if AEs are well managed. Drug holidays may be a key for successfully controlling AEs with DE. DE can be useful for controlling progressive disease with increasing Tg levels.

Clinical Indications for Treatment with Multi-Kinase Inhibitors in Patients with Radioiodine-Refractory Differentiated Thyroid Cancer

Differentiated thyroid cancer is usually a slow-growing disease, even if the patients develop distant metastasis. For recurrent or metastatic disease, radioactive iodine therapy is a standard treatment. However, the disease gradually progresses in some of the patients and can ultimately develop into life-threatening conditions. For patients with progressive radioactive iodine-refractory differentiated thyroid cancer (RR-DTC), multi-kinase inhibitors (MKIs) including sorafenib and lenvatinib prolonged progression-free survival compared with placebo in pivotal randomized phase 3 trials, although the benefit in overall survival has not been clearly confirmed, possibly because the patients who received placebo were permitted to cross-over to lenvatinib upon disease progression. Moreover, the adverse events related to MKIs were not negligible. Therefore, the optimal timing of MKI initiation has long been controversial, and physicians should consider various patient and disease factors. Herein, we comprehensively review the clinical factors that can be helpful in determining the initiation of MKIs for patients with RR-DTC.