Safety and Efficacy of Gabapen for Pediatric (Regulatory Post Marketing Commitment Plan)

Special Investigation Of Gabapen For Pediatric (Regulatory Post Marketing Commitment Plan)

This investigation aims to understand the following issues in pediatric patients, as well as to assess the need of a special investigation and a post-marketing clinical study:

• The frequency of treatment related adverse events.
• The frequency of efficacy assessment.
• Treatment related unlisted adverse events in Japanese Package Insert.
• Risk factors likely to affect the frequency of treatment related adverse event.

Study Overview

• Status: Completed
• Conditions: Epilepsies, Partial
• Intervention / Treatment: Drug: gabapentin

Detailed Description

All the patients whom an investigator prescribes the first gabapentin should be registered consecutively until the number of subjects reaches target number in order to extract patients enrolled into the investigation at random.

• Study Type: Observational
• Enrollment (Actual): 82

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 15 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

The study whom an investigator involving A9451175 prescribes the Gabapentin

Description

Inclusion Criteria:

• All the pediatric subjects (aged 3-15 years) whom an investigator prescribes the first gabapentin (tablets, syrup, and switch to syrup from tablet) should be registered consecutively until the number of subjects reaches target number in order to extract patients enrolled into the investigation at random.

Exclusion Criteria:

• Patients who have been enrolled in the drug use investigation of Gabapen tablets in adults (protocol No. A9451163).
• Patients who receive Gabapen tablets or syrup before, except for switched from tablets to syrup.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Gabapentin; Peadiatric subjects taking Gabapen Tablets and syrup.

Drug: gabapentin; According to Japanese Package Insert: For infants and children aged 3 to 12 years, a daily dosage of 10 mg/kg of gabapentin should be administered orally in 3 divided doses on the first day of treatment, and an effective dosage of 20 mg/kg should be administered to them in 3 divided doses on day 2. From day 3 on, infants aged 3 to 4 years should be maintained on the dosage of 40 mg/kg, and children aged 5 to 12 years on the dosage of 25 to 35 mg/kg administered orally in 3 divided doses, respectively (the maximum daily dosage: 1800 mg). Though the maintenance dosage may be adjusted depending on the patient's condition, the maximum daily dosage should be 50 mg/kg. At any time point, dosage should not exceed that the dosage for adults and children aged 13 years.As for children aged 13 years or over is as same as administration for adult.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment-Related Adverse Events	A treatment-related adverse event was any untoward medical occurrence attributed to gabapentin in a participant who received gabapentin. Relatedness to gabapentin was assessed by the investigator and sponsor (Pfizer Japan Inc.).	MAX 104 weeks
Clinical Efficacy Rate	Clinical efficacy rate, which was defined as the percentage of participants who achieved clinical efficacy over the total number of efficacy analysis population, was presented along with the corresponding exact 2-sided 95% CI. For the basis of efficacy evaluation, frequencies of epileptic seizure were recorded during the previous 4 weeks from the treatment start date, and that from the end date of assessment period. Clinical efficacy was assessed according to the following categories: (1) effective, (2) not effective, or (3) not assessable.	MAX 104 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment-Related Adverse Events Unexpected From Japanese Package Insert	A treatment-related adverse event was any untoward medical occurrence attributed to gabapentin in a participant who received gabapentin. Expectedness of the adverse event was determined according to the Japanese package insert. Relatedness to gabapentin was assessed by the investigator and sponsor (Pfizer Japan Inc.).	MAX 104 weeks
Number of Participants With Risk Factors for Treatment-Related Adverse Events	A treatment-related adverse event was any untoward medical occurrence attributed to gabapentin in a participant who received gabapentin. Participants with treatment-related adverse events were counted by each candidate risk factor (including gender, age, and disease eligible for the survey) to assess whether these were risk factors for the treatment-related adverse events. No inferential analyses of risk factors were performed because of a small number of the events (5 events).	MAX 104 weeks
Number of Participants Who Responded to Treatment With Gabapentin by Baseline Severity of Epileptic Seizure	Participants who responded to the treatment with gabapentin were counted by the baseline severity of epileptic seizure (mild, moderate and severe) to assess whether the baseline severity of epileptic seizure was a factor affecting the treatment efficacy.	MAX 104 weeks
Number of Participants Who Responded to Treatment With Gabapentin by Baseline Frequency of Epileptic Seizure	Participants who responded to the treatment with gabapentin were counted by the baseline frequency of epileptic seizure (<=8 versus >8 episodes/per 4 weeks) to assess whether the baseline frequency of epileptic seizure was a factor affecting the treatment efficacy.	MAX 104 weeks
Number of Participants Who Responded to Treatment With Gabapentin by Number of Concomitant Antiepileptic Drugs at Baseline	Participants who responded to the treatment with gabapentin were counted by the number of concomitant epileptic drugs at baseline across 5 categories (no drug, 1 drug, 2 drugs, 3 drugs, and 4 or more drugs) to assess whether the number of concomitant epileptic drugs at baseline was a factor affecting the treatment efficacy.	MAX 104 weeks
Number of Participants Who Responded to Treatment With Gabapentin by Treatment Period	Participants who responded to the treatment with gabapentin were counted by the treatment period (non-long term [less than 1 year] or long term [1 year or more]) to assess whether the treatment period with gabapentin was a factor affecting the treatment efficacy.	MAX 104 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Key Treatment-Related Adverse Events (Central Nervous System Depressant Actions)	Central nervous system depressant actions including somnolence and ataxia were determined as key survey items by the sponsor (Pfizer Japan Inc.). These events were defined according to MedDRA/J version 17.1 as the events classified in "psychiatric disorders" or "nervous system disorders" of the system organ classes, or those classified in "asthenia" or "gait disturbance" of the preferred terms. A treatment-related adverse event was any untoward medical occurrence attributed to gabapentin in a participant who received gabapentin. Relatedness to gabapentin was assessed by the investigator and sponsor.	MAX 104 weeks
Number of Participants With Key Treatment-Related Adverse Events (Aggressive Behaviors)	Aggressive behaviors including affect lability and hostility were determined as key survey items by the sponsor (Pfizer Japan Inc.). These events were defined as the 101 preferred terms listed by pharmaceuticals and medical devices agency and classified according to MedDRA/J version 17.1. A treatment-related adverse event was any untoward medical occurrence attributed to gabapentin in a participant who received gabapentin. Relatedness to gabapentin was assessed by the investigator and sponsor.	MAX 104 weeks
Response Ratio (R Ratio)	R Ratio was calculated by the following formula, where B represented the baseline frequency of epileptic seizures during the previous 4 weeks from the treatment start date, whereas T represented the frequency of epileptic seizures during the previous 4 weeks from the end of assessment period: R Ratio = (T - B) / (T + B). R Ratio is within the range of -1 to +1, and a negative value represents a reduction in the frequency of seizure.	MAX 104 weeks
Responder Rate	Responder rate, which was defined as the percentage of participants whose R ratio was - 0.333 or less, was presented along with the corresponding exact 2-sided 95% CI. R ratio of - 0.333 or less corresponded to the decrease of epileptic seizure frequency by 50% or more.	MAX 104 weeks
Reduction From Baseline in Epileptic Seizure Frequency	Reduction from baseline in epileptic seizure frequency was defined by the following formula, where B represented the baseline frequency of epileptic seizures during the previous 4 weeks from the treatment start date, whereas T represented the frequency of epileptic seizures during the previous 4 weeks from the end of assessment period: Reduction from baseline in epileptic seizure frequency (%) = [(T-B) / B] X 100. The median percentages were presented along with the corresponding minimum and maximum percentages.	MAX 104 weeks

Collaborators and Investigators

• Sponsor: Pfizer's Upjohn has merged with Mylan to form Viatris Inc.

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start: December 1, 2011
• Primary Completion (Actual): August 1, 2014
• Study Completion (Actual): September 1, 2014

Study Registration Dates

• First Submitted: September 23, 2011
• First Submitted That Met QC Criteria: September 23, 2011
• First Posted (Estimate): September 27, 2011

Study Record Updates

• Last Update Posted (Actual): February 3, 2021
• Last Update Submitted That Met QC Criteria: February 1, 2021
• Last Verified: August 1, 2016

More Information

Terms related to this study

• Keywords: safety; Gabapentin; Epilepsies
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy; Epilepsies, Partial; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Excitatory Amino Acid Antagonists; Excitatory Amino Acid Agents; Tranquilizing Agents; Psychotropic Drugs; Anti-Anxiety Agents; Anticonvulsants; Antimanic Agents; Gabapentin
• Other Study ID Numbers: A9451175