A Study to Evaluate Efficacy and Safety of Light Dose in Subjects With PWB Treated With Hemoporfin PDT

Inclusion Criteria:

1. Subject must be 18 to 75 years of age inclusive, at the time of signing the informedconsent.

2. Subject is Fitzpatrick skin type I-VI.

3. A male subject must agree to use contraception during the Treatment Period and forat least 6 months after the last dose of study treatment and refrain from donatingsperm during this period.

4. A female subject is eligible to participate if she is not pregnant, notbreastfeeding, and at least one of the following conditions applies: Not a woman of childbearing potential (WOCBP) . OR A WOCBP who agrees to follow thecontraceptive guidance during the Treatment Period and for at least 30 days afterthe last dose of study treatment.

5. The subject has a clinical diagnosis of PWB located i) on the extremities, trunk,caudal cervical and/or retroauricular area (Stage One); ii) on the face and/or neck (Stage Two).

6. The longest diameter of the treatment area is ≥3 cm, and the short diameter is ≥2cm.

7. Subject is capable of giving signed informed consent, which includes compliance withthe requirements and restrictions listed in the informed consent form (ICF) and inthis protocol.

8. Subject, in the Investigator's opinion, is in good general health and free of anydisease state or physical condition that may impair the evaluation of PWB or exposethe subject to an unacceptable risk by study participation.

9. If the subject has a history of epilepsy or seizure, the disease must remain stablefor at least 6 months prior to C1D1.

Exclusion Criteria:

1. Subject is pregnant, lactating, or is planning to become pregnant during the study.

2. Subject has plaque/nodular changes and severe hypertrophy within the target PWBarea.

3. Subject has Sturge-Weber syndrome.

4. Subject has any skin pathology or condition that, in the Investigator's opinion,could interfere with the evaluation of the study drug or requires use of interferingtopical, systemic, or surgical therapy.

5. The subject has evidence of scarring within the target PWB area and/or the subjecthas a history of hypertrophic scarring or keloidal scarring.

6. Subject is immunosuppressed related to medication use and/or disease.

7. The subject has clinical abnormalities, as determined by the Investigator, whichmakes them unsuitable for receiving study treatment in the Investigator's opinion atScreening.

8. Subject has received any therapy on the treatment region that, in the Investigator'sopinion, may affect the target PWB area.

9. Subject is known or in the opinion of the Investigator likely to be noncompliantwith the requirements of the study protocol (eg, due to alcoholism, drug dependency,mental incapacity).

10. Subject has a history of either significant neurological events (such as majorstroke) or a mental condition rendering him/her unable to understand the nature,scope, and possible consequences of the study.

11. Subject has an unstable cardiac disease or has any medical condition that in theopinion of the Investigator may worsen from receipt of study treatment or subjectparticipation.

12. The subject has a history of cutaneous photosensitization, porphyria, orphotodermatosis.

13. The subject has the need or has plans to be exposed to artificial tanning devices orexcessive sunlight during the study.