Phentermine for Obesity

(LEAP Trial)

Recruiting at 4 trial locations

Overseen By Amanda Velazquez, MD

Age: 18+

Sex: Any

Trial Phase: Phase 4

Sponsor: Wake Forest University Health Sciences

Must not be taking: MAO inhibitors, Stimulants

Disqualifiers: Heart disease, Glaucoma, Substance use, others

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 24 months

870 Participants Needed

Trial Summary

What is the purpose of this trial?

This trial is studying the long-term effects of the weight-loss drug phentermine on people with obesity. The drug helps by making you feel less hungry and burning more calories. Researchers want to see if it is safe and effective over an extended period. Phentermine has been used in various formulations and combinations for weight loss, showing modest efficacy but with potential cardiovascular and psychiatric side effects.

Do I need to stop my current medications to join the trial?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you have used certain weight-loss or stimulant medications in the past 12 months. It's best to discuss your specific medications with the study team.

What data supports the effectiveness of the drug phentermine for obesity?

Research shows that phentermine can lead to significant weight loss in obese patients, with studies reporting average weight losses of 6.4 kg over 20 weeks and up to 22.4% of initial weight over several months. This suggests that phentermine can be an effective option for weight loss in obese individuals. ^{1 2 3 4 5}

Is phentermine generally safe for humans?

Phentermine has been associated with several side effects, including nausea, dizziness, headaches, and cardiovascular issues like palpitations and atrial fibrillation (irregular heartbeat). Serious adverse events have been reported, such as cardiovascular and kidney complications, and it is important to monitor its use carefully. ^{1 3 6 7 8}

How does the drug Phentermine Hydrochloride 8 MG differ from other obesity treatments?

Phentermine Hydrochloride 8 MG is unique because it is used in lower doses and specifically timed to target high-risk eating periods in the afternoon and evening, which can be beneficial for those who tend to skip breakfast and eat more later in the day. This approach aims to improve weight loss outcomes by aligning with patients' eating patterns. ^{1 2 3 4 9}

Research Team

Jamy Ard, MD

Principal Investigator

Wake Forest University Health Sciences

Nicholas M Pajewski, PhD

Principal Investigator

Wake Forest University Health Sciences

Kristina H Lewis, MD

Principal Investigator

Wake Forest University Health Sciences

Eligibility Criteria

This trial is for English-speaking adults with obesity (BMI 30-44.9 or BMI 27-29.9 with certain health issues) who are willing to follow a treatment plan and have internet access for online therapy. Women must use effective contraception. Exclusions include recent drug abuse, severe kidney/liver disease, past weight control procedures, recent use of similar medications or significant weight changes, certain heart conditions, heavy alcohol use, pregnancy/breastfeeding intentions within two years, mental health hospitalizations in the last two years.

Inclusion Criteria

Has a smartphone or other device with regular internet access

English-speaking

Provision of electronically-signed consent form

Exclusion Criteria

I have glaucoma or am at high risk for it.

I have been diagnosed with dementia or a serious mental illness.

I haven't changed my weight-loss medication dose in the last year.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive 24 mg/day of phentermine or placebo for up to 24 months, with an evidence-based online lifestyle intervention

24 months

Monthly visits for monitoring

Follow-up

Participants are monitored for safety and effectiveness after treatment

6 months

Treatment Details

Interventions

• Online Lifestyle Behavioral Therapy
• Phentermine Hydrochloride 8 MG

Trial Overview The study examines the long-term effects (up to 2 years) of phentermine on weight management and safety compared to an online lifestyle behavioral therapy program without medication. Phentermine has been FDA-approved for short-term use since 1959; this trial seeks data on its extended usage.

Participant Groups

Group I: Phentermine Experimental Treatment 2 Interventions

Participants randomized to active treatment in LEAP will be provided with phentermine hydrochloride 8 mg scored tablets. This formulation of the drug is commercially available and marketed as Lomaira TM.

Group II: Placebo Placebo Group 1 Intervention

Participants randomized to the control arm of LEAP will be provided with placebo tablets consisting of cellulose and corn starch and manufactured to have the same characteristics of the active drug, including size, shape, weight, and sensory perceptions.

Who Is Running the Clinical Trial?

Wake Forest University Health Sciences

Lead Sponsor

Trials

1,432

Recruited

2,506,000+

Weight Watchers International

Industry Sponsor

Trials

23

Recruited

5,100+

WW International Inc

Industry Sponsor

Trials

25

Recruited

5,300+

The University of Texas Health Science Center, Houston

Collaborator

Trials

974

Recruited

361,000+

Biomedical Research Institute of New Mexico

Collaborator

Trials

11

Recruited

2,300+

WW International Inc.

Collaborator

Trials

5

Recruited

1,200+

Kaiser Permanente

Collaborator

Trials

563

Recruited

27,400,000+

National Heart, Lung, and Blood Institute (NHLBI)

Collaborator

Trials

3,987

Recruited

47,860,000+

KVK-Tech, Inc.

Collaborator

Trials

1

Recruited

870+

Johns Hopkins University

Collaborator

Trials

2,366

Recruited

15,160,000+

Findings from Research

A comprehensive analysis of the FDA Adverse Event Reporting System revealed 18,675 unique adverse event reports linked to anti-obesity medications (AOMs) among 15,143 patients, highlighting significant safety concerns.

Serious adverse events included a fatality ratio of 4.9%, with cardiovascular complications being particularly prevalent, accounting for 31% of AEs related to phentermine, and indicating a need for ongoing safety monitoring of AOMs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Descriptive analysis of reported adverse events associated with anti-obesity medications using FDA Adverse Event Reporting System (FAERS) databases 2013-2020. Alsuhibani, A., Alrasheed, M., Gari, M., et al.[2022]

References

1. Germany pubmed.ncbi.nlm.nih.gov

Three- and six-month efficacy and safety of phentermine in a Mexican obese population. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

Lower dosages of phentermine-fenfluramine given in the afternoon: five cases with significant weight loss. [2019]

3. England pubmed.ncbi.nlm.nih.gov

Plasma phentermine levels, weight loss and side-effects. [2014]

4. United States pubmed.ncbi.nlm.nih.gov

A double-blind clinical trial in weight control. Use of fenfluramine and phentermine alone and in combination. [2013]

5. Korea (South) pubmed.ncbi.nlm.nih.gov

The Use of Phentermine for Obesity in Psychiatric Patients With Antipsychotics. [2023]

6. Netherlands pubmed.ncbi.nlm.nih.gov

Descriptive analysis of reported adverse events associated with anti-obesity medications using FDA Adverse Event Reporting System (FAERS) databases 2013-2020. [2022]

7. Italy pubmed.ncbi.nlm.nih.gov

Phentermine-Associated Atrial Fibrillation: A Case Report and Literature Review. [2022]

8. Korea (South) pubmed.ncbi.nlm.nih.gov

Postmarketing surveillance study of the efficacy and safety of phentermine in patients with obesity. [2021]

9. United States pubmed.ncbi.nlm.nih.gov

Obesity pillars roundtable: Phentermine - Past, present, and future. [2023]