Comparing Sarecycline and Doxycycline Effects on the Skin and Gut Bacteria in Acne.

Inclusion criteria

• Diagnosis of acne vulgaris with:

• At least 10 inflammatory lesions (papules, pustules, and nodules) up to 100 noninflammatory lesions (open and closed comedones)
• No more than 2 nodules on the face

Exclusion criteria

• Dermatological condition of face or facial hair that could interfere with clinical evaluations
• Subjects who have used the following medications (topical refers only to the facial area) will not be eligible:

2a) Within 2 week prior to randomization:

• Topical acne medications such as retinoids, antibiotics, hormonal modulators
• Topical benzoyl peroxide
• Topical anti-inflammatories and corticosteroids

2b) Within 4 weeks prior to randomization:

• Systemic antibiotics
• Systemic acne treatments
• Oral probiotic supplement
• Systemic corticosteroids

2c) Within 12 weeks prior to randomization:

• Systemic retinoids

• Individuals who have changed any of their hormonal based contraception or therapies within 3 months prior to joining the study.

• Individuals who are pregnant or breastfeeding.

• Individuals on oral contraceptive pills or progesterone or estrogen containing therapies unless they have been on a stable dose for 2 months.

• Individuals on finasteride or dutasteride

• Current tobacco smoker or a tobacco smoking history that is greater than 5 pack-years.