Allergan Aesthetics announced results from two Phase 4 studies showing improved facial appearance satisfaction in adults using GLP-1 medications for weight management.
Presented at the 2026 American Society for Dermatologic Surgery (ASDS) Annual Meeting, the data suggest multimodal aesthetic treatments can address facial volume loss associated with rapid medical weight loss.
The findings, reported by news.abbvie.com, focus on two specific clinical trials: HARMONY IN DIVERSITY and HALO. These studies investigated how hyaluronic acid (HA) injectables and neurotoxins—substances used to temporarily relax facial muscles—impact patients navigating the physiological changes of GLP-1 therapy.
Clinical implications for medical weight loss
Patients utilizing glucagon-like peptide-1 (GLP-1) receptor agonists often experience significant changes in facial morphology. As weight decreases, the loss of subcutaneous fat can lead to reduced facial volume and altered skin quality, which may influence a patient’s self-perception.
The HARMONY IN DIVERSITY study (Cohort 2) evaluated 30 adults on stable GLP-1 doses. This group received a combination of HA injectables, onabotulinumtoxinA (a neurotoxin), and a study-specified skincare regimen. According to the company, participants reported a mean improvement of 42.4 points in FACE-Q Satisfaction With Facial Appearance at the 30-day mark.
The HALO study provided interim analysis for 25 adults receiving HA injectables across the face. The company reported that these participants saw a 39.6-point mean improvement in FACE-Q scores by month three. 95.7% of these participants expressed satisfaction or very satisfied that they maintained their natural appearance.
In Plain English: The Clinical Takeaway
- Volume Restoration: Injectable fillers (HA) may help mitigate the “sunken” facial appearance sometimes seen during rapid weight loss.
- Multimodal Approach: Combining muscle-relaxing neurotoxins with fillers and skincare may provide more comprehensive results than single-modality treatments.
- Psychological Impact: Improving facial appearance through these treatments showed statistically significant links to improved social and psychological function in study participants.
Researchers used FACE-Q and SKIN-Q to measure outcomes
To ensure scientific rigor, the researchers utilized validated instruments, specifically the FACE-Q and SKIN-Q questionnaires. These tools use a 0-to-100 scale where higher scores represent superior patient-reported outcomes in appearance, skin quality, and emotional well-being.
The research was funded by Allergan Aesthetics, an AbbVie company, as part of a broader scientific program aimed at advancing medical weight loss aesthetics. The following table summarizes the primary outcomes reported in the two Phase 4 studies:
| Study Name | Primary Treatment Modality | Key Metric (Mean Improvement) | Patient Satisfaction/Naturalness |
|---|---|---|---|
| HARMONY IN DIVERSITY (Cohort 2) | HA Injectables + Neurotoxin + Skincare | 42.4 points (FACE-Q) | Statistically significant improvements in skin quality |
| HALO (Interim Analysis) | HA Injectables | 39.6 points (FACE-Q) | 95.7% satisfied with looking like themselves |
While the results showed high satisfaction, the company noted that most treatment-related adverse events were mild, nonserious, and resolved without medical intervention. In the HARMONY IN DIVERSITY cohort, no evidence of distant spread of the neurotoxin was observed.
FDA regulates onabotulinumtoxinA for specific wrinkle indications
The use of onabotulinumtoxinA is strictly regulated by agencies such as the FDA in the United States. While these Phase 4 studies provide valuable real-world evidence for a specific patient population, they do not change the established indications for these products.
OnabotulinumtoxinA is indicated for the temporary improvement of moderate to severe glabellar lines, lateral canthal lines, forehead lines, and platysma bands. However, medical professionals must remain vigilant regarding the potential for “distant spread” of the toxin. According to the official prescribing information, rare instances of toxin spreading to unintended areas can cause symptoms such as muscle weakness, difficulty swallowing, or breathing difficulties.
Because these studies were “open-label,” participants and investigators were aware of the treatments being administered, which is a standard approach in Phase 4 post-marketing studies to observe how products perform in clinical practice.
Avoid treatments during active infection or hypersensitivity
Patients should not undergo neurotoxin or filler treatments if they have an active infection at the proposed injection site or a known hypersensitivity to any component of the formulation. Seek immediate medical attention if you experience any of the following after an injection:
- Difficulty swallowing (dysphagia) or speaking (dysphonia).
- Vision changes, such as double vision (diplopia) or drooping eyelids (ptosis).
- General muscle weakness or breathing difficulties.
- Signs of an allergic reaction, such as hives or swelling.
Patients on GLP-1 medications should consult their primary physician or endocrinologist before undergoing aesthetic procedures to ensure treatment plans align with their metabolic health and weight loss trajectory.
Allergan Aesthetics is evaluating multimodal treatment strategies and skin quality support, including topical exosome-derived serums, to address the needs of the medical weight loss population.
