交叉研究 Crossover study

[The study has ended]

Aim and objectives



  1. 比較需時及每日服藥兩種模式的依從性及性行為的覆蓋程度
  2. 評估使用者對兩種服藥模式的喜惡
  3. 分析服藥後的風險補償行為
  4. 推測不同模式對將來愛滋病毒傳播動力的影響

香港中文大學 – 新界東醫院聯網臨床研究倫理聯席委員會被授權在有需要時審視個人資料藉以評估研究倫理(參考編號:2016.719)。如果你有更多關於臨床 研究倫理相關問題,請與該委員會聯繫(電郵 或 致電 2632 3935)。

The project aims to explore the usage patterns and related determinants of on-demand versus daily mode of PrEP in MSM with substantial risk of HIV infection.

The objectives are, to:

  1. compare the adherence to PrEP and associated protection of sex acts between on-demand and daily mode of delivery
  2. examine the preferred mode of PrEP before and following exposure to periods of two modes of delivery
  3. characterise pattern of risk compensation following PrEP
  4. project transmission dynamics of HIV infection under the influence of different modes of PrEP delivery

The Joint Chinese University of Hong Kong – New Territories East Cluster Clinical Research Ethics Committee has approved this study (Ref. No.: 2016.719) and is authorised to access the participants' records related to the study for ethics review purpose. For enquiry regarding clinical research ethics, please contact the Committee at and phone at 2632 3935.

交叉研究 Crossover study

研究設計 Study design


Participants will be followed up for a total of 50 weeks. PrEP will be prescribed to participants free. For half of the participants, a 16-week course of daily PrEP will be provided, followed by another 16 weeks of on-demand treatment. For the other half of the participants, the sequence is reversed. Participants begin with on-demand PrEP for 16 weeks then switch to daily PrEP in the remaining 16 weeks. All participants are asked to visit the clinic regularly for body check-up, HIV and STI tests, complete questionnaire and collect prescription. At week 50, participants will be contacted for follow-up questionnaire.

參加資格 Eligibility criteria


  1. 為十八歲或以上男性、曾與男性肛交,最近一次於過去6個月內
  2. 經常在港居住
  3. 在未來數月有傾向進行不安全性行為
  4. 沒有感染愛滋病毒 (過去3個月內愛滋病毒抗體測試呈陰性反應)
  5. 乙型肝炎表面抗原呈陰性反應
  6. 腎臟功能正常

To join the study, you must:

  1. be male, aged 18 or above, and had anal sex with another man, with the most recent sex act in the last 6 month; and
  2. normally reside in Hong Kong; and
  3. be inclined to have unprotected anal sex in the coming months; and
  4. be HIV negative (HIV antibody test negative within last 3 months); and
  5. be HBsAg negative; and
  6. have normal renal function

研究流程 Flow chart of the study



  • 腎功能
  • 乙型肝炎表面抗原
  • 愛滋病毒
  • 梅毒、淋病、衣原體


Body check-up & tests:

  • Renal function
  • HBsAg
  • HIV
  • Syphilis, NG/CT

Urine and other samples will be collected.
Fingerprick rapid tests will be performed.

注意: PrEP2研究已經完結。有興趣者可以電郵聯絡
Attention: PrEP1 study has ended. Interested person may contact for updates on new projects.