研究目的

本研究項目旨在探索以乙型腦膜炎球菌疫苗預防淋病感染的應用。

請按此閱讀關於該疫苗的資訊。

Aim

The aim of the study is to assess the efficacy of a meningococcal B (MenB) vaccine against Neisseria gonorrhoeae (NG) infections among men who have sex with men.

Click here for the information of the vaccine.

研究設計

參加者將會被隨機分配到兩組：第一組參加者以肌肉注射方式接種兩劑乙型腦膜炎球菌疫苗，分別在基線和一個月後進行；而另一組參加者會按相同的時間表接受兩劑安慰劑注射(生理鹽水)。

在基線和第二劑疫苗注射前、後將會進行驗血檢查身體的免疫反應。參加者在接受第二劑疫苗注射後的抽血日可獲得港幣200元現金券答謝參與。所有參加者需接受合共約兩年的觀察，期間每三個月自行採集尿液、咽拭子和直腸拭子樣本，以及接受抽血作性病檢測。參加者完成觀察後將會獲贈港幣100元現金券補償交通費用。參加者並不會得悉其獲分配的組別直至一年後，屆時將獲告知所接受的是疫苗或安慰劑。對照組參加者將被邀請接受兩劑疫苗注射。

國際不同研究間接顯示接種乙型腦膜炎球菌疫苗能減低約三成感染淋病的機會。乙型腦膜炎球菌疫苗(Bexsero)在香港是已註冊的藥物，註冊適應症為預防乙型腦膜炎球菌感染。因此，接種該疫苗作預防淋病感染只屬實驗性質。於整個觀察期內，參加者需要每月填答網上問卷，輸入個人背景資料、接受注射後可能產生的副作用和性行為模式。

是次研究的劑藥或有一定副作用，包括但不限於注射位置紅腫或痠痛、頭痛、疲倦、肌肉或關節痛、發熱或發冷和屙嘔肚痛。參與本項研究沒有可預見的心理，生理，社會，法律，或者經濟危險或得益。假使出現任何相關臨床情況，例如性病感染、嚴重副作用，參加者可以選擇被轉介至公營醫療服務作醫學跟進。

Study Design

Participants would be randomly assigned into either intervention or control arm. Subjects in the intervention arm would receive two doses of MenB vaccine by intramuscular injection at baseline and a month after, while control subjects would receive two doses of normal saline with the same schedule.

At baseline and immediately before receiving the second dose, and after the second dose, blood samples would be taken to assess immune responses. After blood taking post-second dose of the vaccine, participants will receive HK$200 cash coupon as a token of appreciation. All participants would be asked to self-collect urine, oropharyngeal and rectal swabs, and to provide blood sample for STI screening for every three months during the 2-year observation period. After the observation period, participants would receive $100 to compensate for transportation costs. Group assignment would not be revealed until 1 year after participation in the study. Participants in the control group would be invited to receive two doses of vaccine.

Studies from different countries have indirectly shown that receiving MenB vaccine might reduce the risk of NG infection by 30%. MenB vaccine (Bexsero) is a registered pharmaceutical product in Hong Kong. Its indication is for preventing meningococcal serogroup B infections. Therefore, receiving the vaccine for preventing NG infection is only experimental. Online questionnaires would be administered for recording one’s demographics, followed by the monitoring of reported adverse reactions, and sexual behaviours on a monthly basis.

The vaccination/placebo used in this study may cause side effects, including but not limited to pain, redness or hardness at the injection site, muscle pain, fatigue, headache, nausea, joint pain, fever, chills, nausea and diarrhoea. Participation is entirely voluntary and will not subject the participants to any foreseeable psychological, physiological, social, legal or commercial risks or benefits. . If any NG- or vaccination-related clinical conditions, e.g. STI, drug reactions, occur requiring medical consultation, referral would be made to specialists in the public service.

時間表

月份	跟進
0	基線問卷、性病測試*、醫學會診、隨機分配組別及接受相應注射(第一劑)
1	問卷、性病測試、醫學會診、接受注射(第二劑)
2	抽血檢查身體的免疫反應
4	問卷、性病測試
7	問卷、性病測試
10	問卷、性病測試
13	問卷、性病測試、醫學會診(接受第一劑注射#^)
14^	(醫學會診、接受第二劑注射^)
15^	(抽血檢查身體的免疫反應^)
16/17^	問卷、性病測試
19/20^	問卷、性病測試
22/23^	問卷、性病測試
25/26^	問卷、性病測試、醫學會診
參加者於研究期間若懷疑感染性病亦可預約到訪進行測試
*基線檢測淋病感染參加者將被邀請完成治療後參與本研究，屆時將由第0月起重新計算
#所有參加者將被告知獲分配組別：對照組參加者將被邀請接受兩劑疫苗注射
^只限對照組參加者

Timetable

Month	Follow up
0	Baseline questionnaire, STI tests*, medical consultation, randomisation, and receive injection (1st dose)
1	Questionnaire, STI tests, medical consultation, randomisation, and receive injection (2nd dose)
2	Blood taking for immunological assessment
4	Questionnaire, STI tests
7	Questionnaire, STI tests
10	Questionnaire, STI tests
13	Questionnaire, STI tests, medical consultation, randomisation, (and receive 1st dose of vaccine#^)
14^	(Medical consultation, receive 2nd dose of vaccine^)
15^	(Blood taking for immunological assessment^)
16/17^	Questionnaire, STI tests
19/20^	Questionnaire, STI tests
22/23^	Questionnaire, STI tests
25/26^	Questionnaire, STI tests, medical consultation
Participants with STI symptoms can make an appointment for STI screening.
*Participants with a baseline gonorrhoea positive test result would be invited to join after completing treatment.
#All participants would be unblinded. Participants in the control group would be invited to receive two doses of vaccine.
^Control group only.

本研究的性病測試

性病測試	樣本採集方法
愛滋病毒抗原及抗體	抽血
梅毒抗體	抽血
淋病	尿液、自行採集直腸拭子、自行採集咽拭子
衣原體	尿液、自行採集直腸拭子、自行採集咽拭子
參加者若確診感染性病可以選擇被轉介至公營醫療服務作醫學跟進

STI tests in this study

STI test	Sample collection method
HIV antigen and antibody	Venesection
Syphilis antibody	Venesection
Gonorrhoea	Urine, self-collected rectal swab, self-collected pharyngeal swab
Chlamydia	Urine, self-collected rectal swab, self-collected pharyngeal swab
Participants diagnosed with an STI would be referred to specialists in the public service.

參加資格

參加者須：

1. 年齡介乎十八歲至五十歲男性、過去六個月曾與男性發生性行為
2. 在港居住
3. 於研究期內能定期到訪研究診所
4. 能閱讀中或英文及以中或英文溝通
5. 具淋病感染的風險因素
6. 適合接種研究使用的疫苗

Eligibility criteria

To join the study, you must:

1. be male, aged between 18 and 50 years, and had sex with another man within the last 6 months; and
2. live in Hong Kong; and
3. be able to attend the research clinic regularly during the observation period; and
4. be able to read Chinese and communicate fluently in Chinese/English; and
5. be at risk of gonorrhoea infection; and
6. be deemed suitable to receive the vaccine being studied.