Inclusion Criteria:

• Have signed the current approved informed consent form.
• Have a clinically or phenotypically defined VM, LM, or mixed VLM affecting the skin.
• Lesion genotyping confirms either PIK3CA or TEK mutations, known to be pathogenic.
• Agrees to use contraception if of childbearing potential.
• Willing and able to comply with the protocol and be available for the entire study.
• Between 18 and 60 years of age.
• Lesion must be amenable to defining a contiguous study treatment area of 140 cm^2.

Exclusion Criteria:

• Lesion to be treated is on the face or involves mucosa.
• Presence of ulcerations on the target-treatment lesion.
• Known systemic hypersensitivity to the VT30 drug substance, its inactive ingredients, or the vehicle.
• Uncontrolled diabetes mellitus.
• Hyperlipidemia that is poorly controlled on current treatment.
• Pregnant or nursing, planning to become pregnant, or planning to father a child during the study.
• History of malignancy except successfully treated nonmetastatic cutaneous squamous cell or basal cell carcinoma and/or localized carcinoma in situ of the cervix.
• Major surgery within 8 weeks of Screening, or a surgical, laser or other procedure involving the target lesion within 8 weeks of Screening, or planned to occur during the study.
• Any other medical or personal condition that, in the opinion of the Investigator, may potentially compromise the safety or compliance of the subject, or may preclude the subject's successful completion of the clinical study.
• Medically significant infection (e.g., cellulitis or abscess, or a systemic infection) within 8 weeks of Screening.
• Ongoing therapy with another topical treatment or any medication that inhibits PI3K, Akt pathway, or the mTOR pathway, or in the opinion of the Investigator, the subject requires systemic therapy for their vascular malformation condition.
• Use of a biologic or systemic immunosuppressive agent within 3 months of Screening.
• Systemic use of corticosteroids, within 30 days of Screening.
• Treatment with a small molecule investigational product within 30 days of Screening, or with any investigational biologic products within 3 months of Screening.
• Positive for hepatitis C antibody, hepatitis B surface antigen, hepatitis B core antibody, or human immunodeficiency virus.
• Alanine transaminase or aspartate transaminase laboratory values in excess of 1.5 x the upper limit of normal at Screening.
• Hemoglobin A1c is > 8%.
• Any other clinically significant laboratory or testing abnormality that, in the opinion of the Investigator, might confound the study, interfere with the subject's ability to complete the study, or represent a meaningful safety risk upon study enrollment.

Eligibility last updated 10/12/21. Questions regarding updates should be directed to the study team contact.