New onset myasthenia gravis in a patient with non small cell lung cancer treated with lorlatinib a novel anti-cancer agent

Safety of lorlatinib in ALK-positive non-small-cell lung cancer and management of central nervous system adverse events

The use of tyrosine kinase inhibitors has made a breakthrough in the treatment of non-small-cell lung cancer (NSCLC). Recently, lorlatinib, a third-generation tyrosine kinase inhibitor, has demonstrated significant systemic and intracranial activity in both first-line and subsequent-line therapy in ALK-positive NSCLC patients. In this review, general characteristics of lorlatinib, its efficacy in the treatment of ALK-positive NSCLC patients and the safety of lorlatinib, particularly addressing central nervous system adverse events, are discussed. Management of central nervous system adverse events, which seem to be specific to lorlatinib therapy, is outlined.

CNS and PNS manifestation in immune checkpoint inhibitors: A systematic review

INTRODUCTION

Immunomodulatory therapies, including the use of immune checkpoint inhibitors (ICIs), have made a profound impact on treatment of advanced cancers in recent decades. Neurologic immune-related adverse events (irAEs) related to use of these agents are rare but potentially fatal sequelae. This systematic reviewed aimed to describe onset, clinical features, treatment, and outcome of neurological irAEs following ICI usage.

METHODS

A systematic literature search was conducted to identify all case reports (n = 168) and case series (n = 29) describing neurological irAEs (n = 255 patients). Patient demographics, clinical features, and clinical courses were extracted and used to assess statistical relationships between reported variables.

RESULTS

Of reports describing neurological irAEs related to ICI use, the majority of cases were in men (66%) and patients above the age of fifty (85%). Disorders of the peripheral nervous system (PNS, 83%) were more common than central nervous system involvement. Neuromuscular disorders were the most common type of neurological irAE (e.g. myasthenia gravis, 36%), followed by peripheral neuropathies (16%), followed by all CNS disorders combined (15%). Most cases presented within the first 5 doses of ICI treatment. Most patients improved clinically, but 24% of cases were fatal. Mortality was highest in patients with neuromuscular irAEs, such as myasthenia gravis and myositis.

CONCLUSION

This systematic literature review describes the largest collection of neurological irAEs to date including both CNS and PNS manifestations of ICIs. The information described herein can be used to better inform monitoring and treatment of patients undergoing treatment with ICIs.

Postmarketing safety of anaplastic lymphoma kinase (ALK) inhibitors: an analysis of the FDA Adverse Event Reporting System (FAERS)

Background

Inhibitors of the anaplastic lymphoma kinase (ALK) gene mutation are highly effective treatments for ALK-positive lung cancer. We conducted this pharmacovigilance analysis using the Food and Drug Administration Adverse Event Reporting System (FAERS).

Patients and methods

FAERS files from 2012 to 2020 were used. Reports for crizotinib, ceritinib, alectinib, brigatinib, and lorlatinib were filtered. We used the Medical Dictionary for Regulatory Activities (MedDRA version 22.1). Further, we searched for adverse events on the preferred term (PT) level based on case reports in the literature. After filtering duplicate reports, disproportionality analysis was used to detect safety signals by calculating proportional reporting ratios (PRRs), reporting odds ratios (RORs), empirical Bayesian geometric mean, and information component. Reports were considered statistically significant if the 95% confidence interval did not contain the null value.

Results

Within the system organ classes, significant safety signals were found, including those for crizotinib [eye disorders (PRR 2.09, ROR 2.12)], ceritinib [gastrointestinal disorders (PRR 2.19, ROR 2.41), hepatobiliary disorders (PRR 4.4, ROR 4.52), respiratory disorders (PRR 1.96, ROR 2.08)], alectinib [hepatobiliary disorders (PRR 2.60, ROR 2.63)], brigatinib [respiratory disorders (PRR 2.15, ROR 2.31)], and lorlatinib [metabolism disorders (PRR 3.34, ROR 3.53)]. For adverse events on the PT level, we found several significant signals, including pneumothorax with crizotinib (PRR 3.29, ROR 3.29), ceritinib (PRR 3.13, ROR 3.13), and alectinib (PRR 4.88, ROR 4.89); myasthenia gravis with lorlatinib (PRR 6.05, ROR 6.05); photosensitivity reactions with crizotinib (PRR 2.20, ROR 2.20), ceritinib (PRR 4.30, ROR 4.31), alectinib (PRR 20.43, ROR 20.51), and brigatinib (PRR 20.97, ROR 21.05); pulmonary arterial hypertension with brigatinib (PRR 2.92, ROR 2.92) and lorlatinib (PRR 9.2, ROR 9.24); and rectal perforation with crizotinib (PRR 7.83, ROR 7.83). All the detected safety signals were confirmed using Bayesian methods.

Conclusion

ALK inhibitors differed in their safety profile reports. We found several significant safety signals that matched previously published case reports, including pulmonary arterial hypertension, rectal perforation, myasthenia gravis, and photosensitivity. These signals require further regulatory investigation to determine their significance and potentially update the product labels to inform patients and clinicians.

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ALK inhibitors differed in their safety profile reports. We found several significant safety signals.

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These signals include pulmonary arterial hypertension, rectal perforation, myasthenia gravis, and photosensitivity.

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Further regulatory investigations are required to determine the significance of these signals and update the product labels.

Neuromuscular Complications of Targeted Anticancer Agents: Can Tyrosine Kinase Inhibitors Induce Myasthenia Gravis? Getting Answers From a Case Report up to a Systematic Review

More than 40 tyrosine kinase inhibitors (TKIs) have received hematological or oncological indications over the past 20 years, following the approval of imatinib, and many others are currently being tested in clinical and preclinical level. Beyond their common toxicities, no certain agent from this large class of molecularly targeted therapies was strongly associated with “off-target” impairment of neuromuscular transmission, and although myasthenia gravis (MG) is a well-characterized autoimmune disorder, only few sporadic events proven by serologically detected causative autoantibodies and/or by positive electrophysiological tests are reported in the literature. Herein, we present the first case of anti-MUSK (+) MG in a woman with metastatic BRAF-mutant melanoma after long-term treatment with dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor). Triggered by this report, a systematic literature review was conducted, summarizing all other cancer cases that developed MG, after exposure to any type of targeted agent and regardless of the underlying malignancy. All available data on the clinical diagnosis, the potential of administered TKIs to induce a seropositive myasthenic syndrome, the immune and non-immune-mediated pathogenesis of postsynaptic damage, and the challenging management of this neuromuscular toxicity were collected and discussed. In the presented case, MG was confirmed by both autoantibodies and nerve-conduction tests, while its reactivation after TKIs rechallenge supports a more than coincidental association. The following review identified 12 cancer cases with TKI-related MG in six case reports and one case series. In most of them, the myasthenia diagnosis was challenging, since the clinical symptomatology of fatigable weakness was not corroborating with consistent laboratory and electrophysiological findings. In fact, anti-AchR titers were positive in five and anti-MuSK only in the abovementioned individual. The symptomatology corresponded to TKI discontinuation and standard treatment with pyridostigmine and prednisolone; intravenous immunoglobulin was added only in three, and two required mechanical ventilation. In an era where TKIs will be prescribed more frequently for various malignancies, even in combinations with immune-checkpoint inhibitors, this report synthesizes their risk for neuromuscular complications and increases the clinicians’ awareness in order to extend the on-treatment and overall survival of TKI-treated cancer patients.

Drugs That Induce or Cause Deterioration of Myasthenia Gravis: An Update

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder which is characterized by presence of antibodies against acetylcholine receptors (AChRs) or other proteins of the postsynaptic membrane resulting in damage to postsynaptic membrane, decreased number of AChRs or blocking of the receptors by autoantibodies. A number of drugs such as immune checkpoint inhibitors, penicillamine, tyrosine kinase inhibitors and interferons may induce de novo MG by altering the immune homeostasis mechanisms which prevent emergence of autoimmune diseases such as MG. Other drugs, especially certain antibiotics, antiarrhythmics, anesthetics and neuromuscular blockers, have deleterious effects on neuromuscular transmission, resulting in increased weakness in MG or MG-like symptoms in patients who do not have MG, with the latter usually being under medical circumstances such as kidney failure. This review summarizes the drugs which can cause de novo MG, MG exacerbation or MG-like symptoms in nonmyasthenic patients.