Expert Discusses the ‘Four Pillars of Acne Pathogenesis’

LAS VEGAS — For clinicians who rely on generic tretinoin 0.5% as their go-to treatment for patients with acne, Shanna Miranti, MPAS, PA-C, offers some straightforward advice: You can do better.

“Friends don’t let friends write generic tretinoin only because there are so many better options out there,” Miranti, who practices dermatology in Naples, Florida, said at the Society of Dermatology Physician Associates (SDPA) 22nd Annual Fall Dermatology Conference. “Don’t get lazy; your patients deserve better.”

In her wide-ranging presentation, Miranti described the four pillars of acne pathogenesis as increased sebum production caused by androgens, follicular hyperkeratinization in the pilosebaceous unit, colonization by Cutibacterium acnes (formerly Proprionibacterium acnes), and inflammation. Acne “starts with androgens, but this is a cascade, so you have to find treatment options that hit as many of these four pillars as possible,” Miranti explained. “If you’re only using generic tretinoin, you’re only hitting maybe two of the four pillars at best.”

She then discussed the best treatment options for each pillar:

Follicular plugging and hyperkeratinization. Topical retinoids, including tretinoin, adapalene, tazarotene, and trifarotene, are highly effective for this issue. Systemic isotretinoin is also a strong option. For patients who are pregnant or trying to conceive, azelaic acid is a helpful alternative.

Excessive sebum production and androgens. “This may be the genesis of when acne begins — during puberty,” Miranti said. “With rising androgens comes rising amounts of sebum.” The only topical treatment that specifically targets this is clascoterone (Winlevi), which should be applied twice daily. For systemic management of excessive sebum, isotretinoin is highly effective. In women, spironolactone (50 mg daily, or split into two doses) and oral contraceptives are also options.

Inflammation. Topical options include retinoids, antibiotics, benzoyl peroxide (BPO), topical dapsone, azelaic acid, and clascoterone. Systemic options include isotretinoin; the antibiotics doxycycline, minocycline, and sarecycline; spironolactone; and oral contraceptives. “So, when you see patients with intense inflammation, and they’re starting to get post-inflammatory erythema or post-inflammatory hyperpigmentation, you need something to address this inflammatory problem,” she noted.

C acnes. Topical treatment options include BPO and antibiotics. However, topical antibiotics should never be used alone, Miranti said; they must always be combined with BPO to prevent bacterial resistance. Oral options include sarecycline, “which has a low propensity for antibiotic resistance and spares the gut microbiome to some degree,” and the “old school” antibiotics doxycycline, minocycline, and tetracycline. “But all oral antibiotics should be used concomitantly with BPO,” she said.

Regardless of which treatment is chosen for any pillar, Miranti emphasized that monotherapy with a single agent is often insufficient. “Historically, we have combined therapies to treat the multiple causes of acne,” she said. “The average number of acne products used per patient is 2.53, but that’s also the average number of copays. We have to be conscious of that. If you are a mom with four kids who are on acne medication, you want to minimize your copay burden. So, if you can find a topical medication that hits three out of the four pillars of acne pathogenesis, that would be fantastic.” The only topical that targets excess sebum is clascoterone, she noted, and the only medication that hits all four pillars is isotretinoin.

In October 2023, the US Food and Drug Administration approved a once-daily topical gel for patients aged 12 years or older that contains clindamycin 1.2%, adapalene 0.15%, and BPO 3.1%. The first-ever triple combination therapy, known as Cabtreo, was released to pharmacies in March 2024. In a phase 2 trial, researchers randomized 394 patients aged 9 years or older with moderate to severe acne to once-daily IDP-126, one of three dyad combination gels, or vehicle gel for 12 weeks. Patients in the Cabtreo arm achieved significantly greater lesion reductions than those in the vehicle arm (inflammatory: 78.3% vs 45.1%; noninflammatory: 70.0% vs 37.6%; P

In a network meta-analysis, researchers reviewed 221 randomized controlled trials to compare the efficacy of pharmacologic treatment for acne. The most effective treatment in reducing inflammatory and noninflammatory lesions was oral isotretinoin, followed by Cabtreo.

Miranti disclosed being a speaker, consultant, and/or an advisory board member for Arcutis Biotherapeutics, Bausch Health, Dermavant Sciences, Galderma, Incyte Corporation, LEO Pharma, Eli Lilly and Company, Sun Pharma, Swift USA, and Verrica Pharmaceuticals.