Azitra explores recombinant filaggrin for post-weight-loss skin firmness

Azitra, a biopharmaceutical company, is developing a clinically backed anti-aging ingredient with potential applications for post GLP-1 skin laxity. The ingredient, ATR-COSF, utilizes a novel supernatant formulation that contains an active recombinant human domain of the protein filaggrin (rHDfilaggrin) for cosmetic and skin care applications.

Recent ex vivo studies on ATR-COSF demonstrate “promising” applications in treating laxity in defatted skin, indicating potential alignment for use following sudden weight loss. The findings outline areas of formulation for the Staphylococcus epidermidis (S. epidermidis) derived ingredient in precision dermatology, and cosmetic proteins and peptides.

Personal Care Insights speaks to Travis Whitfill, PhD, co-founder and COO at Azitra, who tells us that, according to the findings, the precise delivery of recombinant filaggrin into the dermal layers can improve skin quality through elasticity and barrier strength.

He says that testing the ingredient’s properties on defatted skin helps establish its applicability in GLP-1-related skin care solutions, as the testing mimics the interaction with the loss of subcutaneous fat.

Fliggrain for the skin

Filaggrin is a protein that is critical to the upkeep of skin elasticity and pliability and healthy appearance. The ATR-COSF program utilizes the supernatant from a strain of S. epidermidis, a bacterium that naturally resides on human skin. The bacterium isAzitra's ATR-COSF targets skin elasticity and barrier strength. engineered to secrete a functional unit of the human filaggrin protein.

The recent research utilized fresh, healthy human skin explants and demonstrated a significant increase in rHDfilaggrin delivered through the stratum corneum — the outermost layer of the epidermis — and into the stratum granulosum — a thin epidermis layer below the outermost layer — compared to a single-dose previous work.

“The ex vivo findings support the idea that precisely delivering recombinant filaggrin into the stratum corneum and stratum granulosum can help restore key elements of barrier integrity and elasticity in filaggrin‑deficient skin,” says Whitfill.

“By replenishing a protein that is central to hydration, pliability, and barrier function, targeted filaggrin delivery has the potential to improve skin firmness and resilience and, in turn, soften the appearance of fine lines and early wrinkles in aging or environmentally stressed skin.”

Tackling skin laxity after weight loss

According to Whitfill, the use of the defatted-skin model in testing is relevant to GLP-1-related applications because it mimics conditions where subcutaneous fat is reduced, and the overlying skin must maintain elasticity with less structural support.

“The improvements seen in that model suggest ATR-COSF could have utility in helping skin better withstand laxity and wrinkle formation in settings such as rapid weight loss, including GLP-1-associated changes,” he says.

He clarifies that the studies did not set out to research GLP-1-related applications in the early ex vivo studies.Ex vivo findings suggest potential applications for post GLP-1 skin laxity.

“GLP-1 facial aging was not a primary, predefined indication for these early ex vivo studies; it is an emerging, hypothesis-generating application that will need to be tested specifically in Azitra’s future work.”

Whitfill explains that when it comes to Filaggrin delivery in personal care applications, it is most realistically positioned to address skin-level concerns. These may be barrier compromise, dryness, reduced elasticity, and fine lines that arise when the epidermis and upper dermis are not sufficiently hydrated and structurally supported.

“It is not designed to replace lost deep fat volume or correct major contour changes in the mid-face. In GLP-1-related aging, ATR-COSF could help improve surface firmness, texture, and fine wrinkling, but would have inherent limitations in treating volumetric hollowing or more severe sagging that typically require volumizing or lifting interventions,” he elaborates.

Next steps for ATR-COSF include continued formulation optimization, additional ex vivo wrinkle and defatted-skin models. The biopharmaceutical company will then move into the human studies phase. These will focus on visible wrinkle reduction and improvements in elasticity and barrier function.

“To translate the current data into a commercially viable skin care ingredient, Azitra will need clinical evidence in humans showing statistically and cosmetically meaningful improvements in wrinkles, firmness, and barrier metrics. [It will also need] safety and tolerability data with repeat topical use across diverse skin types; and dose, regimen, and formulation validation that can be manufactured consistently at scale,” Whitfill concludes.

Avoiding haphazard GLP-1 claims

The personal care market is teeming with GLP-1-relevant claims as beauty players race to take part in the weight loss drug rush. Segments ranging from beauty supplements, topical solutions, and even laser hair removal are pondering how to capitalize on the weight loss golden goose.

As splinter categories making GLP-1 adjacent claims emerge, scientific rigor and claim substantiation are proving to be increasingly crucial.

For example, Kourtney Kardashian’s wellness brand, Lemme, recently came into hot water for allegedly making misleading marketing claims related to its Lemme GLP-1 Daily weight-loss capsule. The class-action lawsuit alleges that the company employed “deceptive marketing practices” and falsely advertised appetite suppression properties without adequate clinical backing.

The class-action underlines the precarious positioning of unsubstantiated clinical efficacy claims in an avalanching GLP-1 market.