As of May 4, 2023, out of the 4,336 subjects enrolled, 1% (20 participants) are still ongoing in the study, and 99% (4,316 participants) have completed their study. The only site with active participants remaining is site 520, which will conduct their final follow-up visit in May 2023.

Regarding the end-of-study subjects, a total of 3,485 subjects have already completed the study until the 36th follow-up month. There are 506 subjects lost to follow-up, 248 who have passed away, 32 who have withdrawn their consents, 38 who have moved to a city without a PROACTIVE Site, 5 who tested negative for HIV, and 2 who are currently suspended (imprisoned). Figure 1 illustrates the study progress at each site, while Table 1 provides a list of completed study participants.

After the completion of the follow-up period, the Sites will make preparations for the last monitoring visit and site closeout visit. All last monitoring visits will be concluded by May 2023. In June 2023, several sites are scheduled for the closeout visits, including site 510, 590, 600, 640, and 650. Other sites will have their visits scheduled in the subsequent months. In anticipation of these visits, sites are required to fulfill all study-related aspects mentioned in the closeout visit checklist. These include completing the Case Report Form/Source Documents, providing all Adverse Event/Serious Adverse Event/Unanticipated Problem reports, managing data, organizing the Site Regulatory Binder, maintaining logs, equipment, supplies, and handling specimens.

For sites that have undergone the closeout visit, the archiving of study documents will be carried out within one month after the visit. These documents will be retained for a period of five years following the completion of the study.

Figure 1. Site’s Study Progress
Table 1. Subjects’ End of Study Reasons

As of May 4, 2023, out of the 700 participants who enrolled in the study, 166 (23.71%) have ended their participation, while 533 (76.14%) are still ongoing. The study is being conducted at three different sites, and all sites are currently on visit 4. The details of each site’s visits are listed in Table 1.

It is worth mentioning that the study has had some difficulties keeping participants. Out of the 167 subjects who ended their participation, 106 (15.14%) completed the study, while 44 (6.29%) withdrew from the study due to personal reasons or loss of interest. Reasons for withdrawal also included participant decision. Additionally, some participants did not receive the complete vaccine regimen within 12 months of enrollment, which resulted in three (0.43%) subjects being excluded from the study. Two (0.29%) subjects were not allowed to continue because continuation was not in their best inter-est, and one (0.14%) subject was non-compliant with study procedures. Unfortunately, one (0.14%) subject passed away during the study, and ten (1.43%) subjects had other reasons for ending their participation.

Furthermore, the study has been tracking symptomatic visits among participants. Table 2 provides the details of these visits as of May 4, 2023 . It is important to note that while some participants have experienced COVID-19 symptoms, this does not necessarily mean that they have contracted the disease.

Table 1. Details of Visits per site per March 6, 2023

Table 2. Symptomatic Visit Details per May 4, 2023