Convulsive Seizure Due to Hypomagnesemia Caused by Short-term Vonoprazan Intake

Severe Hypomagnesemia in a Patient Treated Using Carboplatin Co-Administered with Vonoprazan

Introduction

We describe a case of severe hypomagnesemia that occurred during treatment with carboplatin (CBDCA) and nanoparticle albumin-bound paclitaxel (nab-PTX) for lung adenocarcinoma when co-administered with vonoprazan.

Case Presentation

A man in his 70s was diagnosed with stage IIIA lung adenocarcinoma and received CBDCA and nab-PTX as the first-line treatment. The patient had been taking omeprazole 10 mg once daily (for >3 years) for gastroesophageal reflux disease, but it was switched to lansoprazole 15 mg because of hospital's adopted medication. During the first treatment cycle, his serum creatinine levels increased from 1.0 to 1.5 mg/dL, suggesting CBDCA-associated renal impairment. Because of gastric discomfort on day 15 of the second cycle, lansoprazole was switched to vonoprazan 10 mg once daily. On day 23 of the second cycle, he developed torsades de pointes and was hospitalized; severe hypomagnesemia (0.4 mg/dL) was detected to be causing the symptoms. Discontinuation of vonoprazan and a single intravenous infusion of 60 mEq magnesium sulfate raised serum magnesium levels to 3.7 mg/dL, and the arrhythmia disappeared. Mild hypomagnesemia (1.4 mg/dL) reappeared 5 days later, and an additional intravenous infusion of 20 mEq magnesium sulfate with subsequent oral magnesium oxide (1,980 mg/day) resolved the symptoms. CBDCA was discontinued and nab-PTX monotherapy was continued. Vonoprazan was resumed owing to gastric discomfort relapse; however, grade ≥2 hypomagnesemia did not reappear later.

Conclusions

This case highlights the risk of severe hypomagnesemia in patients with CBDCA and vonoprazan co-administration; therefore, regular monitoring of serum magnesium levels during the treatment is crucial.

Safety of potassium-competitive acid blockers in the treatment of gastroesophageal reflux disease

INTRODUCTION

Proton pump inhibitors (PPIs) are the first-line treatment for gastroesophageal reflux disease (GERD). However, due to their intrinsic limitations, there are still unmet clinical needs that have fostered the development of potassium-competitive acid blockers (P-CABs). Currently, four different drugs (vonoprazan, tegoprazan, fexuprazan, and keverprazan) are marketed in some Asian countries, whereas only vonoprazan and tegoprazan are available in Western countries (USA and Brazil or Mexico, respectively).

AREAS COVERED

This review summarizes the current knowledge on P-CABs acute and long-term safety in GERD treatment compared to that of PPIs. Full-text articles and abstracts were searched in PubMed.

EXPERT OPINION

P-CABs proved to address some of the unmet clinical needs in GERD, with a favorable risk-benefit ratio compared to conventional PPIs. Preclinical and clinical findings have highlighted P-CAB safety to be superimposable, to that of PPIs, in short-term treatments, although further studies are warranted to monitor their effects in long-term therapy. From an epidemiological point of view, the paucity of rigorous data for many variables (e.g. age, ethnicity, drug interactions, comorbidities, genetic polymorphisms, interindividual susceptibility, and gut dysbiosis) deserves a worldwide framework of continuous pre/post-marketing pharmacovigilance programs to reduce potential confounding factors and accurately link acute and chronic P-CAB therapy to adverse outcomes.

Emerging Long-Term Risks of the Use of Proton Pump Inhibitors and Potassium-Competitive Acid Blockers

Acid-related disorders represent a significant global health burden. Pharmacological treatment of these conditions has at times been challenged and limited by incomplete effectiveness, antibiotic resistance, adverse medication effects and/or interactions, and disease recurrence. Since the early 1990s, the mainstay of treatment has been proton pump inhibitors (PPIs). Recently, the US Food and Drug Administration issued a clearance for vonoprazan, a potassium-competitive acid blocker (PCAB). PCABs are a new class of acid-suppressing agents that may overcome some of these challenges. The aim of this review is to evaluate and compare the emerging long-term risks of PPI and PCAB therapies.

The role of vonoprazan in patients with erosive esophagitis

Acid suppression is the primary therapy for erosive esophagitis (EE). Although proton pump inhibitors (PPIs) are considered as the first-line medication for EE, 10-20% of patients with Los Angeles C and D grade EE do not gain complete mucosal healing and symptom control despite 8-week double-dose PPI treatment. Vonoprazan is a novel potassium-competitive acid blocker (P-CAB), which blocks the H+, K+-adenosine triphosphatase enzymes in a K+-competitive and reversible manner. Vonoprazan exhibits different pharmacological and pharmacokinetic profiles from conventional PPIs, and has a rapid, potent and sustained acid inhibitory effect. In this review, we summarized and discussed current evidence regarding the role of vonoprazan in terms of mucosal healing, maintaining remission and symptom relief for the management of EE, including the initial and maintenance treatment of EE, as well as for PPI-resistant EE patients. Safety concerns and cost-effectiveness analysis of vonoprazan were also mentioned in the article. As a potent and well-tolerated acid blocker, vonoprazan has the potential to become a novel option for the management of EE.