This study is a long-term follow-up study for patients who have been administered AAV2hAQP1 in the Phase 1 Open-Label, Dose Escalation Study to Determine the Optimal Dose, Safety, and Activity in Subjects with Radiation Induced Parotid Gland Hypofunction and Xerostomia

This clinical trial is designed to assess the long-term safety and activity of intra-parotid administration of AAV2hAQP1 in subjects with radiation-induced parotid salivary hypofunction and xerostomia.

After completion of their Month 12 Follow-Up visit in Study MGT016, subjects will be invited to enroll in this 4-year follow-up study during which they will be assessed for up to 60 months following study drug administration. This follow-up trial is a non-interventional study designed to collect data on longer-term safety and activity at 18, 24, 36, 48, and 60 months following study drug administration.

Over the course of the study, subjects will undergo physical and oral examinations; vital sign measurements; weight measurements; AE assessments; concurrent medication assessments; sample blood collection for hematology and chemistry; urinalysis; ear, nose, and throat (ENT) screening for malignancy; imaging assessments (if indicated); salivary flow assessments; and questionnaire assessments.

Inclusion Criteria:

1. Are willing and able to provide informed consent
2. Received AAV2hAQP1 administered via Stensen's duct to a single or both parotid glands in the prior open-label, Phase 1, dose-escalation study (Study MGT016)
3. Are willing and able to adhere to the protocol and long-term follow-up

Exclusion Criteria:

1. Subjects unwilling or unable to meet with the requirements of the study will be excluded

Subjects with radiation induced parotid gland hypofunction and xerostomia who have particpated in the MGT016 AAV2hAQP1 study.