OUP accepted manuscript

Treatment of metastatic ALK-positive non-small cell lung cancer: real-world outcomes in a single center study

Background

Rearrangement in anaplastic lymphoma kinase (ALK) occurs in 4-7% of non-small cell lung cancer (NSCLC) cases. Despite improved survival with tyrosine kinase inhibitors (TKIs), treatment resistance remains challenging. This retrospective study analyzed advanced ALK-positive NSCLC patients, focusing on clinical aspects, treatments, resistance, and outcomes.

Methods

Patients diagnosed between January 2009 and December 2021 who received at least one ALK-TKI line at the Karolinska University Hospital, were included. We evaluated crizotinib or 2nd generation ALK-TKI effectiveness in first-line treatment and lorlatinib in subsequent lines. Overall survival (OS) was defined as from the date of advanced lung cancer diagnosis until the date of last follow-up (April 22, 2022) or the date of death from any cause. Progression-free survival (PFS), from the date of starting ALK-TKI until the date of progression, death, or last follow-up. Resistance mechanisms were assessed through re-biopsies utilizing next-generation sequencing (NGS).

Results

Out of 160 eligible patients, 10 were excluded. Median follow-up was 54.0 months from diagnosis and 45.0 months from initial ALK-TKI treatment. Crizotinib showed a median PFS of 8.0 months and a median OS of 35.0 months. Second generation ALK-TKIs demonstrated a median PFS of 52.0 months [OS was not reached (NR)]. Overall, the median OS was 65.0 months. Poor prognostic factors included male sex, thromboembolism, crizotinib treatment, and chronic obstructive pulmonary disease (COPD)/asthma. Rebiopsies in 18 cases revealed secondary ALK mutations in 8 patients, correlating with a shorter median PFS in subsequent ALK-TKI treatment (1.0 vs. 7.0 months).

Conclusions

This comprehensive study, spanning over a decade, provides crucial insights into the clinical characteristics, treatment patterns, and resistance mechanisms of advanced ALK-positive NSCLC, where median OS exceeds 5 years. Re-biopsies during treatment are essential for advancing our understanding of resistance mechanisms and the tumor dynamics evolving during ALK-TKI therapy.

ALK Inhibitor Treatment Patterns and Outcomes in Real-World Patients with ALK-Positive Non-Small-Cell Lung Cancer: A Retrospective Cohort Study

BACKGROUND

Randomized trials have demonstrated that anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) can be safe and efficacious treatments for patients with ALK-positive advanced non-small-cell lung cancer (aNSCLC). However, their safety, tolerability, effectiveness, and patterns of use in real-world patients remain understudied.

OBJECTIVE

We sought to assess the overall treatment pattern characteristics, safety, and effectiveness outcomes of real-world patients with ALK-positive aNSCLC receiving ALK TKIs.

PATIENTS AND METHODS

This retrospective cohort study using electronic health record data included adult patients with ALK-positive aNSCLC receiving ALK TKIs between January 2012 and November 2021 at a large tertiary medical center, University of California, San Francisco (UCSF), with alectinib or crizotinib as the initial ALK TKI therapy. Our primary endpoints included the incidence of treatment changes (treatment dose adjustments, interruptions, and discontinuations) during the initial ALK TKI treatment, the count and type of subsequent treatments, rates of serious adverse events (sAEs), and major adverse events (mAEs) leading to any ALK TKI treatment changes. Secondary endpoints included the hazard ratios (HRs) for median mAE-free survival (mAEFS), real-world progression-free survival (rwPFS), and overall survival (OS) when comparing alectinib with crizotinib.

RESULTS

The cohort consisted of 117 adult patients (70 alectinib and 47 crizotinib) with ALK-positive aNSCLC, with 24.8%, 17.9%, and 6.0% experiencing treatment dose adjustments, interruptions, and discontinuation, respectively. Of the 73 patients whose ALK TKI treatments were discontinued, 68 received subsequent treatments including newer generations of ALK TKIs, immune checkpoint inhibitors, and chemotherapies. The most common mAEs were rash (9.9%) and bradycardia (7.0%) for alectinib and liver toxicity (19.1%) for crizotinib. The most common sAEs were pericardial effusion (5.6%) and pleural effusion (5.6%) for alectinib and pulmonary embolism (6.4%) for crizotinib. Patients receiving alectinib versus crizotinib as their first ALK TKI treatment experienced significantly prolonged median rwPFS (29.3 versus 10.4 months) with an HR of 0.38 (95% CI 0.21-0.67), while prolonged median mAEFS (not reached versus 91.3 months) and OS (54.1 versus 45.8 months) were observed in patients receiving alectinib versus crizotinib but did not reach statistical significance. Yet, it is worth noting that there was a high degree of cross-over post-progression, which could significantly confound the overall survival measures.

CONCLUSIONS

We found that ALK TKIs were highly tolerable, and alectinib was associated with favorable survival outcomes with longer time to adverse events (AE) requiring medical interventions, disease progression, and death, in the context of real-world use. Proactive monitoring for adverse events such as rash, bradycardia, and hepatotoxicity may help further promote the safe and optimal use of ALK TKIs in the treatment of patients with aNSCLC.

Sustained Improvement in the Management of Patients with Non-Small-Cell Lung Cancer (NSCLC) Harboring ALK Translocation: Where Are We Running?

ALK translocation amounts to around 3-7% of all NSCLCs. The clinical features of ALK+ NSCLC are an adenocarcinoma histology, younger age, limited smoking history, and brain metastases. The activity of chemotherapy and immunotherapy is modest in ALK+ disease. Several randomized trials have proven that ALK inhibitors (ALK-Is) have greater efficacy with respect to platinum-based chemotherapy and that second/third generation ALK-Is are better than crizotinib in terms of improvements in median progression-free survival and brain metastases management. Unfortunately, most patients develop acquired resistance to ALK-Is that is mediated by on- and off-target mechanisms. Translational and clinical research are continuing to develop new drugs and/or combinations in order to raise the bar and further improve the results attained up to now. This review summarizes first-line randomized clinical trials of several ALK-Is and the management of brain metastases with a focus on ALK-I resistance mechanisms. The last section addresses future developments and challenges.

Real-World Treatment Sequencing, Toxicities, Health Utilities, and Survival Outcomes in Patients with Advanced ALK-Rearranged Non-Small-Cell Lung Cancer

OBJECTIVES

This real-world analysis describes treatment patterns, sequencing and clinical effectiveness, toxicities, and health utility outcomes in advanced-stage, incurable ALK-positive NSCLC patients across five different ALK-TKIs.

MATERIALS AND METHODS

Clinicodemographic, treatment, and toxicity data were collected retrospectively in patients with advanced-stage ALK-positive NSCLC at Princess Margaret Cancer Centre. Patient-reported symptoms, toxicities, and health utilities were collected prospectively.

RESULTS

Of 148 ALK-positive NSCLC patients seen July 2009-May 2021, median age was 58.9 years; 84 (57%) were female; 112 (76%) never-smokers; 54 (47%) Asian and 40 (35%) white; 139 (94%) received at least one ALK-TKI: crizotinib (n = 74; 54%) and alectinib (n = 61; 44%) were administered mainly as first-line ALK-TKI, ceritinib, brigatinib and lorlatinib were administered primarily after previous ALK-TKI failure. Median overall survival (OS) was 54.0 months; 31 (21%) patients died within two years of advanced-stage diagnosis. Treatment modifications were observed in 35 (47%) patients with crizotinib, 19 (61%) with ceritinib, 41 (39%) with alectinib, 9 (41%) with brigatinib and 8 (30%) with lorlatinib. Prevalence of dose modifications and self-reported toxicities were higher with early versus later generation ALK-TKIs (P<.05). The presence of early treatment modification was not negatively associated with progression-free survival (PFS) and OS analyses.

CONCLUSION

Serial ALK-TKI sequencing approaches are viable therapeutic options that can extend quality of life and quantity-of-life, though a fifth of patients died within two years. No best single sequencing approach could be determined. Clinically relevant toxicities occurred across all ALK-TKIs. Treatment modifications due to toxicity may not necessarily compromise outcomes, allowing multiple approaches to deal with ALK-TKI toxicities.