Inconsistent condom use among HIV-positive women in the "Treatment as Prevention Era": data from the Italian DIDI study

Consistent condom use among Botswana's female population and associated factors

BACKGROUND

Botswana is one of the countries severely impacted by the HIV/AIDS pandemic. Despite an extensive HIV prevention campaign, the incidence of HIV, particularly among women, remains high. Condoms play a significant role in preventing new HIV infections, although men and women do not consistently use them.

OBJECTIVE

The study assessed the individual, relationship and community factors associated with consistent condom use among women in Botswana.

DESIGN

A cross-sectional study using secondary data drawn from a national survey on Gender-Based Violence Indicators in 2012.

METHODS

The primary survey sampled 639 women, aged 18 years and older, using a multistage procedure. The final sample size for the secondary analysis included a total of 480 women who were sexually experienced and had reported using condoms with their male partners. Multivariate logistic regression analysis was employed to assess the association between consistent condom use and the explanatory variables. The multivariate logistic regression adjusted for cluster/community random effects.

RESULTS

About 43% of the women used condoms consistently in the past year. Consistent condom use was more likely among women who were employed in the past year (adjusted odds ratio = 1.77; 95% confidence interval = 1.25-2.50). While, women who lived with their partners (adjusted odds ratio = 0.46; 95% confidence interval = 0.28-0.74), had non-Christian beliefs (adjusted odds ratio = 0.52; 95% confidence interval = 0.29-0.92), perceived that their partners would be angry if they ask to use a condom (adjusted odds ratio = 0.19; 95% confidence interval = 0.06-0.58) and perceived that their community says women need their husband's permission to do paid work (adjusted odds ratio = 0.56; 95% confidence interval = 0.38-0.83) were less likely to use condoms consistently.

CONCLUSION

Consistent condom use among Botswana's female population is suboptimal. Consistent condom use was higher among women with employment, and lower among women who lived with their partners, had non-Christian beliefs, feared their partners' reaction upon asking for condom use and held inequitable community gender beliefs. To enhance women's consistent use of condoms, friendly condom use information, female economic empowerment strategies and programmes that involve religious leaders and promote progressive and healthy masculine practices in Sexual Reproductive Health/HIV interventions should be considered.

Condom Use among HIV-Positive Postnatal Women in Primary Health Care Facilities in Tshwane Sub-District 1, Gauteng Province, South Africa

Condoms have been and are still an important part of HIV preventative measures worldwide, and many countries have designed programmes that encourage their use. Consistent and correct condom use among HIV-positive individuals is important in preventing multiple infections. Hence, the uptake and determining factors associated with condom use were investigated in this study. This study was aimed at determining the level of, and factors associated with, condom use among HIV-positive postnatal women in primary health care facilities in Tshwane sub-district 1, Gauteng Province, South Africa. A descriptive cross-sectional study was conducted among 326 HIV-positive postnatal women aged between 15 and 50 years who were conveniently selected and voluntarily participated in the study. A self-developed pretested questionnaire was used to collect data on level of condom use and factors associated with its use from the selected participants. Statistical tests of correlation were then used to determine the association between frequency of condom use during sexual encounter and condom use at last sexual encounter with the independent variables. Regular condom use during sexual encounters was reported by 63.2% of the participants while 83% of the participants reported using a condom at their last sexual encounter. Frequency of condom use during sexual encounter was found to be associated with employment status (p < 0.05), residence (p < 0.001), number of children (p < 0.05), first HIV diagnosis (p < 0.05) and disclosure of HIV status to partner (p < 0.05). Condom use at last sexual encounter was also found to have a significant statistical association with level of education (p < 0.05) and the ability to negotiate condom use (p < 0.001). A good proportion of the participants used condoms regularly. Interventions to improve condom use among this population should focus on female empowerment by investing in their education, and economic empowerment to improve their economic status, which, in turn, would help the women to better negotiate condom use. The other factors mentioned above should also be considered when developing health education policies and programmes about condom use amongst HIV-positive postnatal women.

HIV risk behavior and associated factors among people living with HIV/AIDS in Ethiopia: A systematic review and meta-analysis

Background

HIV risk behavior among people living with HIV/AIDS (PLWHA) is a major public health concern as it increases HIV transmission. In Ethiopia, findings regarding HIV risk behavior have been inconsistent and inconclusive. Therefore, this meta-analysis aimed to estimate the pooled prevalence of HIV risk behavior and associated factors among PLWHA in Ethiopia.

Methods

International databases, including Google Scholar, Cochrane library, HINARI, Pub Med, CINAHL, and Global Health were systematically searched to identify articles reporting the prevalence of HIV risk behavior and associated factors among PLWHA in Ethiopia. The data were analyzed using STATA/SE version-14. The random-effects model was used to estimate the pooled effects. I-squared statistics and Egger’s test were used to assess the heterogeneity and publication bias respectively.

Results

A total of 4,137 articles were reviewed and fourteen articles fulfilling the inclusion criteria were included in this meta-analysis. The pooled prevalence of HIV risk behavior in Ethiopia was 34.3%% (95% CI: 28.2, 40.3). Severe heterogeneity was observed between the included research articles (I² = 96.6, p = 0.000). Alcohol use (OR = 1.9, 95%, CI: [1.6, 2.3]), HIV status non-disclosure (OR = 2.3, 95% CI: [1.3, 4.0]) and perceived stigma (OR = 2.3, 95% CI: [1.3, 4.1]) had a significant association with HIV risk behavior.

Conclusion

The prevalence of HIV risk behavior among PLWHA in Ethiopia was high. Alcohol use, HIV status non-disclosure, and perceived stigma had a significant association with HIV risk behavior. In addition to promoting access to Antiretroviral Therapy (ART) treatment and improving medication adherence among PLWHA, various intervention programs focusing on the associated factors have to be implemented to tackle high-risk sexual behavior and go forward toward ending the HIV/AIDS pandemic.

Consistent condom utilization and associated factors among HIV positive clients attending ART clinic at Pawi general hospital, North West Ethiopia

Background

Human immunodeficiency virus (HIV) affects a highly significant number of people and is responsible for the deaths of many people in sub-Saharan African countries alone. The best prevention method for this virus is through consistent condom utilization which can help to prevent drug-resistant HIV infection and acquisition of new infection. Therefore, this study aimed to assess consistent condom utilization and associated factors among HIV-positive individuals attending an antiretroviral therapy clinic at Pawi general hospital, North West Ethiopia in 2020.

Methods

An institutional based cross-sectional study was conducted among 419 HIV-positive individuals who have follow-up in the Pawi general hospital antiretroviral therapy clinics, from January to February 2020. The study subjects were reached using a systematic sampling technique and data were collected using a pretested and structured questionnaire. Data entry and analysis were performed using epi-data version 3.1 and SPSS version 23 respectively. Binary and multivariable analyses with a 95% confidence level were performed. In the final model, variables with P < 0.05 were considered statistically significant.

Results

A total of 419 antiretroviral therapy study participants were participated in the study with a response rate of 100%. In this finding, the consistent condom utilization rate was 49.2% [95% CI: 42.2–56.5%]. After controlling for possible confounding factors, the results showed that place of residence [AOR = 2.16, 95% CI: 1.05, 4.45], marital status [AOR = 0.19, 95%CI: 0.05, 0.67], number of partners [AOR = 0.19, 95% CI: 0.07, 0.55] and level of education [AOR = 5.33, 95% CI: 1.57, 18.08] were associated factors of consistent condom utilization.

Conclusion

Consistent condom utilization among HIV-positive clients attending antiretroviral therapy clinics at Pawi general hospital was low. Residence, marital status, level of education and number of partners were significantly associated factors of consistent condom use. Health education program and counseling services should be started to increase knowledge about way of transmission and appropriate use of condoms, increase self-efficacy towards condom use and reduction in the number of sexual partners.

The Magnitude and Associated Factors of Consistent Condom Utilization Among ART Users in Hawassa City, Sidama, Ethiopia

BACKGROUND

Antiretroviral therapy (ART) introduction has sharply decreased mortality and morbidity rates among HIV-infected patients and resulted in longer and healthier lives among people living with HIV. Hence, the aim of this study is to determine the level of consistent condom use and associated factors among ART users in Hawassa City.

METHODS

Cross-sectional study design triangulated with qualitative phenomenology was used. One hospital and one health center were selected by simple random sampling and proportional to size allocation was used to assign participants to each health facility. Accordingly, 358 study subjects were selected. Adjusted odds ratio (AOR) with 95% confidence interval was used to implicate significant factors. Thematic content analysis was used and narrative report writing with a quote was used to present qualitative data.

RESULTS

The prevalence of consistent condom utilization in this study was 51.4%. Sex (AOR= 4.20, 95% CI: 2.386, 7.41), residence (AOR=3.55, 95% CI: 1.81, 6.99) educational status (AOR=0.4, 95% CI: 0.196, 0.946), perception on ART's does not reduction of HIV transmission (AOR=1.96, 95% CI: 1.12, 3.43), rate of counseling (AOR=0.37, 95% CI: 0.17, 0.84) and use condom to prevent pregnancy (AOR=4.53, 95% CI: 2.11, 9.73) were found to be independent predictors of consistent condom utilization among ART users. Refusal by husbands, decrement in satisfaction, gender difference with more women than men willing to use consistently and religious reasons were factors associated with inconsistent condom utilization in the qualitative study.

CONCLUSION AND RECOMMENDATION

Consistent condom utilization among ART users was low. Sex, residence, educational status, perception towards ART were significantly associated with consistent condom utilization. Moreover, husband refusal, religious reason, decrement in satisfaction on the qualitative study were associated with non-consistent use of a condom. The importance of consistent condom use should be well addressed in HIV/AIDS patients, to prevent transmission and multiple infections of HIV.

Prevalence of and Factors Associated With Inconsistent Condom Use With HIV-Discordant Male Regular Sex Partners Among HIV-Infected Women in China

This study was to investigate the prevalence and associated factors of inconsistent condom use with HIV-discordant regular male sex partners (RP: defined as their husband or steady boyfriends) in the last six months among HIV-infected women in China. We interviewed 256 HIV-infected women who currently had at least one HIV-discordant RP and had had sexual intercourse with such RP since diagnosis. The prevalence of inconsistent condom use with HIV-discordant RP was 48.4%. Associated factors included perceptions related to condom use and perceived competence in communicating with HIV-discordant RP regarding condom use.

The Prevalence of HIV Load Suppression and Related Factors Among Patients on ART at Phedisong 4 Clinic, Pretoria, South Africa

Background:

Globally, the benefits of viral load suppression in improving the lives of people living with HIV/AIDS have been established. In 2010, the South African Government decentralised ART to the primary care level. This study intended to determine the effect of this decentralisation in achieving viral load suppression among patients.

Objective:

To determine the prevalence of HIV viral load suppression and factors related to the suppression among patients initiated on ART at Pedisong 4 clinic, Tshwane District in Pretoria.

Methods:

A prospective cohort study was conducted on 98 patients initiated on ART between 01 November 2012 and 30 April 2013. Based on the viral load results, they were divided into those who achieved Viral Load Suppression (VLS), and those who did not (NVLS). Analyses were done using SAS® (version 9.2) for Microsoft software. A p < 0.05 was considered significant.

Results:

Ninety patients (91.8%; 95%CI, 84.7% – 95.8%) achieved viral load suppression while eight (8.2%; 95%CI, 4.2% – 15.3%), did not. Of the 98 patients, 63 (64%) were female. In the NVLS group, the female to male ratio was 7:1 (p = 0.038). There was no relationship between viral load suppression and patients’ baseline characteristics, behavioural characteristics and clinical characteristics (p > 0.05). ART adherence reported in both patient groups was ≥ 87.0%.

Conclusion:

There was good viral load suppression in patients initiated on ART at Pedisong 4 clinic. Patients’ baseline, behavioural and clinical characteristics were not related to viral load suppression, necessitating further large sample size studies in various health facilities.

Condomless Sex Among Virally Suppressed Women With HIV With Regular HIV-Serodiscordant Sexual Partners in the Era of Treatment as Prevention

BACKGROUND

Sexual HIV transmission does not occur with sustained undetectable viral load (VL) on antiretroviral therapy (ART). Awareness of ART prevention benefits and its influence on condom use among women with HIV (WWH) remain unexplored. We estimated prevalence and correlates of condomless sex with regular HIV-serodiscordant partners among WWH with undetectable VL on ART.

METHODS

We used baseline questionnaire data from the community-based longitudinal Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS). We included WWH self-reporting vaginal/anal sex with ≥1 HIV-negative/unknown status regular partner within 6 months, and undetectable VL (<50 copies/mL) on ART. We excluded participants exclusively reporting female partners or missing condom-use data. Condomless sex was defined as <100% condom use within 6 months. The primary explanatory variable was awareness of ART prevention benefits. Logistic regression identified factors independently associated with condomless sex.

RESULTS

Of 271 participants (19% of the CHIWOS cohort), median age was 41 (interquartile range: 34-47), 51% were in a relationship, 55% reported condomless sex, and 75% were aware of ART prevention benefits. Among women aware, 63% reported condomless sex compared with 32% of women not aware (P < 0.001). Factors independently associated with condomless sex included being aware of ART prevention benefits (adjusted odds ratio: 4.08; 95% confidence interval: 2.04 to 8.16), white ethnicity, ≥high-school education, residing in British Columbia, and being in a relationship.

CONCLUSIONS

Virally suppressed women aware of ART prevention benefits had 4-fold greater odds of condomless sex. Advancing safer sex discussions beyond condoms is critical to support women in regular serodiscordant partnerships to realize options for safe and satisfying sexuality in the Treatment-as-Prevention era.

Awareness, discussion and non-prescribed use of HIV pre-exposure prophylaxis among persons living with HIV/AIDS in Italy: a Nationwide, cross-sectional study among patients on antiretrovirals and their treating HIV physicians

Background

Before Pre-Exposure Prophylaxis (PrEP) was officially recommended and made available, a few surveys among gay and bisexual men, and persons living with HIV/AIDS (PLWHA), identified an informal use of antiretrovirals (ARVs) for PrEP among HIV-negative individuals. Before PrEP availability in Italy, we aimed to assess whether PLWHA in Italy shared their ARVs with HIV-negative individuals, whether they knew people who were on PrEP, and describe the level of awareness and discussion on this preventive measure among them and people in their close circle.

Methods

Two anonymous questionnaires investigating personal characteristics and PrEP awareness, knowledge, and experience were proposed to HIV specialists and their patients on ARVs in a one-week, cross-sectional survey (December 2013–January 2014). Among PLWHA, a Multivariable Logistic Regression analysis was conducted to identify factors associated with PrEP discussion with peers (close circle and/or HIV associations), and experience (use in close circle and/or personal ARV sharing).

Results

Eighty-seven specialists in 31 representative Infectious Diseases departments administered the questionnaire to 1405 PLWHA. Among specialists, 98% reported awareness, 65% knew the dosage schedule, and 14% had previously suggested or prescribed PrEP. Among PLWHA, 45.6% were somehow aware, discussed or had direct or indirect experience of PrEP: 38% “had heard” of PrEP, 24% were aware of studies in HIV-negative individuals demonstrating a risk reduction through the use of ARVs, 22% had discussed PrEP, 12% with peers; 9% reported PrEP use in close circle and 1% personal ARV sharing. Factors predictive of either PrEP discussion with peers or experience differed between men and women, but across all genders were mainly related to having access to information, with HIV association membership being the strongest predictor.

Conclusions

At a time and place where there were neither official information nor proposals or interventions to guide public policies on PrEP in Italy, a significant number of PLWHA were aware of it, and approximately 10% reported PrEP use in their close circle, although they rarely shared their ARVs with uninfected people for this purpose. Official policies and PrEP availability, along with implementation programs, could avoid risks from uncontrolled PrEP procurement and self-administration practices.

Electronic supplementary material

The online version of this article (10.1186/s12879-017-2819-5) contains supplementary material, which is available to authorized users.

Factors associated with inconsistent condom use among people living with HIV/Aids

OBJECTIVE

to analyze the prevalence and factors associated with inconsistent use of condoms among people living with HIV/ Aids (PLWHA).

METHOD

it is a cross-sectional study with 228, with individual interviews conducted in 2011. A multivariate analysis was performed with a logistic regression model.

RESULTS

143 participants met the inclusion criteria, and the prevalence of inconsistent condom use was 28.7%. However, there was greater adherence among men (79.3%). In the multivariate analysis, the independent variable daily use of alcohol (OR=11.02; 95% CI 1.84, 65.92; p = 0.021) was associated with inconsistent condom use. The chance of men making consistent condom use was higher than women (OR = 0.36, 95% CI 0.15, 0.81; p = 0.015).

CONCLUSION

the prevalence of inconsistent condom male use among PLWHA was low, however, evidenced greater compliance among men over women with a statistically significant difference and the daily use of alcohol was associated with inconsistent condom use.

Cross-sectional comparative study of risky sexual behaviours among HIV-infected persons initiated and waiting to start antiretroviral therapy in rural Rakai, Uganda

OBJECTIVES

To compare risky sexual behaviours between HIV-positive persons initiated on antiretroviral therapy (ART) (ART-experienced) and persons waiting to start on ART (ART-naive) and assess predictors of risky sexual behaviours among HIV-infected patients in rural Rakai district, Uganda.

STUDY DESIGN

This is a cross-sectional study that used data from the Rakai Community Cohort Study (RCCS) database between 2013 and 2014. A structured questionnaire was used for data collection. We used stepwise logistic regression as an index to estimate the adjusted ORs for the association between risky sexual behaviours and ART treatment status.

STUDY SETTING

This study was conducted in Rakai district, located in south-western Uganda. The data for this study were extracted from the RCCS. RCCS is an open prospective cohort of approximately 15 000 consenting participants aged 15-49 years.

PARTICIPANTS

HIV-positive participants aged 18-49 years who had sex at least once a month with any partner prior to the start of the study.

MAIN OUTCOME MEASURES

Inconsistent/no condom use in the last 12 months, alcohol use at last sexual encounter, and two or more sexual partners.

RESULTS

ART-naive participants were more likely to report inconsistent condom use (OR=1.74, 95% CI 1.11 to 2.73) and more likely to drink alcohol at last sexual encounter (OR=1.65, 95% CI 1.11 to 2.46), compared with ART-experienced patients. ART treatment status (p<0.001) was a significant predictor of risky sexual behaviours. Both marital status (p=0.016) and occupation level (p=0.009) were positively associated with inconsistent condom use, while sex (p<0.001) correlated with alcohol use at last sexual encounter.

CONCLUSION

ART-naive participants were more likely to exhibit risky sexual behaviours than the ART-experienced participants. The intensity of risk reduction counselling should be increased for HIV-positive persons waiting to start ART but already in HIV care.

Behavioral interventions to promote condom use among women living with HIV: a systematic review update

Behavioral interventions have been essential components of HIV prevention approaches, especially those aimed to promote safe sexual practices. We conducted a comprehensive literature search without language restrictions between 1980 and July 2014 to identify randomized controlled trials or controlled studies investigating behavioral interventions which: included women living with HIV; focused on condom use promotion; presented/analyzed outcomes by gender; used a 3-month follow-up or more; and considered at least one HIV-related behavioral or biological outcome. Eight studies comprising a total of 1,355 women living with HIV were included in the meta-analyses, and 13 studies were qualitatively described. When compared to standard care or minimal support intervention, behavioral interventions did not demonstrate an effect on increasing consistent condom use at the 3-month follow-up (RR = 0.92; 95%CI: 0.73, 1.16; p = 0.48), 6-month follow-up (RR = 1.13; 95%CI: 0.96, 1.34; p = 0.15), and 12-month follow-up (RR = 0.91; 95%CI: 0.77, 1.08; p = 0.30). Behavioral interventions also failed to reach positive effect in reduction of unprotected sexual intercourse at 6-months (MD = -1.80; 95%CI: -4.21, 0.62; p = 0.14) and 12-months follow-up (MD = -1.39; 95%CI: -2.29, 0.21; p = 0.09). These findings should be interpreted with caution since they are based on a few small trials. New researches are needed to assess the potential gains from a combination of interventions that promote safe sexual behavior with a harm reduction and gender approach, particularly in developing countries where HIV infection rates remain high.

Use of functional genomics to understand replication deficient poxvirus-host interactions

High-throughput genomics technologies are currently being used to study a wide variety of viral infections, providing insight into which cellular genes and pathways are regulated after infection, and how these changes are related, or not, to efficient elimination of the pathogen. This article will focus on how gene expression studies of infections with non-replicative poxviruses currently used as vaccine vectors provide a global perspective of the molecular events associated with the viral infection in human cells. These high-throughput genomics approaches have the potential to lead to the identification of specific new properties of the viral vector or novel cellular targets that may aid in the development of more effective pox-derived vaccines and antivirals.

Prevalence and predictors of facing a legal obligation to disclose HIV serostatus to sexual partners among people living with HIV who inject drugs in a Canadian setting:a cross-sectional analysis

BACKGROUND

In October 2012, the Canadian Supreme Court ruled that people living with HIV must disclose their HIV status before sex that poses a "realistic possibility" of HIV transmission, clarifying that in circumstances where condom-protected penile-vaginal intercourse occurred with a low viral load (< 1500 copies/mL), the realistic possibility of transmission would be negated. We estimated the proportion of people living with HIV who use injection drugs who would face a legal obligation to disclose under these circumstances.

METHODS

: We used cross-sectional survey data from a cohort of people living with HIV who inject drugs. Participants interviewed since October 2012 who self-reported recent penile-vaginal intercourse were included. Participants self-reporting 100% condom use with a viral load consistently < 1500 copies/mL were assumed to have no legal obligation to disclose. Logistic regression identified factors associated with facing a legal obligation to disclose.

RESULTS

We included 176 participants, 44% of whom were women: 94% had a low viral load, and 60% self-reported 100% condom use. If condom use and low viral load were required to negate the realistic possibility of transmission, 44% would face a legal obligation to disclose. Factors associated with facing a legal obligation to disclose were female sex (adjusted odds ratio [OR] 2.19, 95% confidence interval [CI] 1.13-4.24), having 1 recent sexual partner (v. > 1) (adjusted OR 2.68, 95% CI 1.24-5.78) and self-reporting a stable relationship (adjusted OR 2.00, 95% CI 1.03-3.91).

INTERPRETATION

Almost half the participants in our analytic sample would face a legal obligation to disclose to sexual partners under these circumstances (with an increased burden among women), adding further risk of criminalization within this marginalized and vulnerable community.

Women living with HIV still lack highly effective contraception: results from the ANRS VESPA2 study, France, 2011

OBJECTIVES

Advances in antiretroviral treatment (ART) have led to improvements in reproductive health for women living with HIV. This paper aims to investigate the pattern of contraceptive use among women living with HIV in France.

STUDY DESIGN

Data were drawn from the ANRS VESPA2 study, which included a representative sample of HIV-positive people. Contraception methods were documented, including condoms, highly effective contraception methods (HEC) and traditional methods. We measured the frequency of not using any modern contraception (neither condoms nor HEC) and of HEC use and studied their correlates (i.e., geographic origin, age, parity, partnership status, education level, material deprivation, employment status, health insurance, visits to a gynecologist, being on ART, cardiovascular risk) among women at risk of an unintended pregnancy.

RESULTS

Of the 662 women of reproductive age, 327 were in need of contraception. Overall, 20.5% used HEC, 58.8% used condoms and 20.7% used traditional or no methods, with no difference according to geographic origin [sub-Saharan African (SSA) women vs. French and other migrant women]. Among SSA women, being <30years old [odds ratio (OR) 16.39, 95% confidence interval (95%CI) 2.77-97.01], having had at least one child (OR 3.75, 95%CI 1.75-8.04) and being employed (OR 2.36, 95%CI 0.99-5.61) were associated with HEC use; among French and other migrant women, HEC use was associated with being in a stable partnership (OR 4.5, 95%CI 1.2-17.2) and material deprivation (OR 3.3 95%CI 1.4-9.8). Gynecologist visits, health insurance status and cardiovascular risk were not associated with HEC use.

CONCLUSIONS

Condoms remained the predominant contraceptive method despite the absence of restrictions on hormonal contraception and intrauterine device use for HIV-positive women. The recent recommendations about dual method protection should be actively promoted, targeting HIV-positive women, HIV specialists and gynecologists to overcome the barriers to effective contraception.

IMPLICATIONS

The information provided in this study constitutes a major contribution to comprehensively inform the scientific community on contraception practices among women living with HIV in France in the early 2010s. Our results show that the therapeutic advances since the late 1990s and the removal of restrictions on hormonal contraception use have not led to the expected shift in contraception patterns. There is an urgent need to promote dual method protection, as condom use may decrease in the future in the context of the preventive effect of ART.

Priming with a simplified intradermal HIV-1 DNA vaccine regimen followed by boosting with recombinant HIV-1 MVA vaccine is safe and immunogenic: a phase IIa randomized clinical trial

Background

Intradermal priming with HIV-1 DNA plasmids followed by HIV-1MVA boosting induces strong and broad cellular and humoral immune responses. In our previous HIVIS-03 trial, we used 5 injections with 2 pools of HIV-DNA at separate sites for each priming immunization. The present study explores whether HIV-DNA priming can be simplified by reducing the number of DNA injections and administration of combined versus separated plasmid pools.

Methods

In this phase IIa, randomized trial, priming was performed using 5 injections of HIV-DNA, 1000 μg total dose, (3 Env and 2 Gag encoding plasmids) compared to two “simplified” regimens of 2 injections of HIV-DNA, 600 μg total dose, of Env- and Gag-encoding plasmid pools with each pool either administered separately or combined. HIV-DNA immunizations were given intradermally at weeks 0, 4, and 12. Boosting was performed intramuscularly with 10⁸ pfu HIV-MVA at weeks 30 and 46.

Results

129 healthy Tanzanian participants were enrolled. There were no differences in adverse events between the groups. The proportion of IFN-γ ELISpot responders to Gag and/or Env peptides after the second HIV-MVA boost did not differ significantly between the groups primed with 2 injections of combined HIV-DNA pools, 2 injections with separated pools, and 5 injections with separated pools (90%, 97% and 97%). There were no significant differences in the magnitude of Gag and/or Env IFN-γ ELISpot responses, in CD4+ and CD8+ T cell responses measured as IFN-γ/IL-2 production by intracellular cytokine staining (ICS) or in response rates and median titers for binding antibodies to Env gp160 between study groups.

Conclusions

A simplified intradermal vaccination regimen with 2 injections of a total of 600 μg with combined HIV-DNA plasmids primed cellular responses as efficiently as the standard regimen of 5 injections of a total of 1000 μg with separated plasmid pools after boosting twice with HIV-MVA.

Trial Registration

World Health Organization International Clinical Trials Registry Platform PACTR2010050002122368