Our Global Director of Clinical Virology Development, Romina Quercia, advocates for the needs of women living with HIV

Women make up over half of all people living with HIV worldwide yet are under-represented when it comes to clinical trials. Romina Quercia and Annemiek De Ruiter explain what we’re doing to address this.

Today, out of all the key populations affected by the HIV epidemic, women make up more than half (52%) of all people living with HIV worldwide [1] and HIV/AIDS is now the leading cause of death globally for women aged 15-44.

In low and middle-income countries, the statistics around incidence of HIV in women are even starker. Gender inequalities and harmful practices that promote unsafe sex and limit access to health services mean young women in sub-Saharan Africa are often prevented from gaining access to HIV treatment and do not have the final say in their own healthcare decisions. As a consequence, the prevalence of HIV among girls and young women is more than double that of similarly aged males.[2]

Romina Quercia, Global Director of Clinical Virology Development, ViiV Healthcare specialises in the study of HIV in women:

Although HIV in women is a serious and significant issue, women remain largely underrepresented in HIV clinical trials. A large proportion of HIV clinical trials and cure-related research take place in developed countries, where the HIV epidemic is predominantly driven by men who have sex with men. [3]

The under-representation of women in HIV clinical trials leads to gaps in scientific knowledge about how HIV in women may behave differently in men. These variations can affect the safety and efficacy of treatment, including how medicines may interact differently with the female body. [4] Current guidelines for treatment using anti-retrovirals (ARVs) lack specific guidelines for women because they are based on research conducted predominantly in a male population.


  • HIV-positive women have higher CD4 T cell counts and lower plasma HIV RNA levels
  • There is a growing body of information identifying key biological factors that are likely to be partially responsible for the observed sex-based differences in addition to socio-economic differences affecting HIV acquisition and disease progression
  • Differences in immunologic responses to HIV infection, mediated through sex hormones and genetic variation, have been implicated as possible mechanisms. Women more frequently report ART side effects and ART discontinuation compared to HIV-positive males which may be important in accelerating the disease progression of HIV in women.
  • Factors such as body weight, fat distribution, intestinal absorption, protein binding and affinity, metabolism and excretion, and other metabolic functions differ between sexes might affect the distribution of the HIV reservoir within the body.



How can we understand more about HIV in Women?

The lack of enrolment of women in HIV clinical trials prevents study findings from being truly relevant to women. If gender-specific biological markers are not set up and relevant questions are not asked (or are unable to be answered due to a small percentage of women taking part in studies), how can we confidently treat women living with HIV?

Competing priorities for women, which can include childcare, home responsibilities and shift-driven jobs, often make traditional recruitment practices for HIV clinical trials less successful and lead to a gender imbalance in studies.[3] In addition, too often, budgetary and time constraints limit the ability of study sites to develop women-friendly recruitment strategies, and therefore limit their ability to engage with women.[16]

Closing the research gap for HIV in Women

Targeted enrolment of women in clinical trials and careful, separate analysis of data for men and women are crucial to gaining further insights into gender-based differences in HIV infection, to designing sex-specific approaches to HIV treatment and in the future, to potential elimination of the virus through cure or remission.

Increasing female recruitment into HIV studies is not a simple task and the scientific community is the main driver to take action in order to address the shortfall. Getting to zero requires basic science, clinical and social research plans, and increased efforts to work in a coordinated manner to obtain scientific data that can inform ways to curb the HIV epidemic progression that today targets young women.

Annemiek De Ruiter, Head of Global Medical Science, ViiV Healthcare says there’s no simple solution to correcting these issues related to HIV in women:


If you look worldwide, over 50% of people living with HIV are women, across the globe.  If you look at most clinical trials looking at antiretroviral drugs, to see how they work, it tends to be largely done in men.

There’s no one simple solution, but we make sure that we remain a company with a reputation for at least trying to get this right, at least setting up studies to include women, and encouraging our recruiters to include women. So, if there are issues around getting from A to B, or if they need childcare, or something like that, those are some of the things that we can put in place.

We conduct trials not necessarily just in one country or in one part of the world, but we tend to conduct trials in different parts of the world, so that we reflect the global epidemic - not only in terms of gender - but also in terms of geography. 

Our commitment to understanding HIV in women

Recognising the impact of the HIV epidemic on girls and women, ViiV Healthcare is putting specific emphasis on this population as part of our HIV clinical trials strategy and community partnerships programmes.

We contribute knowledge to fill gaps and reach unmet medical needs through our research programmes to understanding more about HIV in women. We have and continue to undertake and support numerous HIV clinical trials specifically among women, with more than 2,100 women taking part in our treatment studies and 300 women in prevention clinical trials.[19]

We also work to address pressing societal challenges through our Positive Action for Girls and Women programme, which is designed specifically to help tackle the harmful cultural norms that limit the aspirations of girls and women and increase their vulnerability to HIV. We are supporting community responses that change attitudes, behaviours and interventions to improve health and rights for girls and women.


[1] UNAIDS. Core Epidemiology Slides. Available at: http://www.unaids.org/en/resources/documents/2016/core-epidemiology-slides. Last accessed July 2016

[2] UNAIDS and African AIDS Union. Empower young women and adolescent girls: Fast-track the end of the AIDS Epidemic in Africa. Available at: http://www.unaids.org/sites/default/files/media_asset/JC2746_en.pdf. Last accessed: July 2015.

[3] Curno, J. Mirjam et al. A Systematic Review of the Inclusion (or Exclusion) of Women in HIV Research: From Clinical Studies of Antiretrovirals and Vaccines to Cure Strategies. JAIDS Journal of Acquired Immune Deficiency Syndromes: 1 February 2016. Vol 71, Issue 2. Last accessed June 2016.

[4] British HIV Association. British HIV Association guidelines for the treatment of HIV-1-positive adults with antiretroviral therapy 2015. Available at http://www.bhiva.org/documents/Guidelines/Treatment/2015/2015-treatment-guidelines.pdf Last accessed July 2016

[5] Meditz AL, MaWhinney S, Allshouse A, Feser W, Markowitz M, Little S, et al. Sex, race, and geographic region influence clinical outcomes following primary HIV-1 infection. J Infect Dis. 2011;203(4):442_51.

[6] Currier J, Averitt Bridge D, Hagins D, Zorrilla CD, Feinberg J, Ryan R, et al. Sex-based outcomes of darunavir-ritonavir therapy: a single-group trial. Ann Intern Med. 2010;153(6):349_57.

[7] Moore AL, Mocroft A, Madge S, Devereux H, Wilson D, Phillips AN, et al. Gender differences in virologic response to treatment in an HIV-positive population: a cohort study. J Acquir Immune Defic Syndr. 2001;26(2):159_63.

[8] Gandhi M, Aweeka F, Greenblatt RM, Blaschke TF. Sex differences in pharmacokinetics. Annual Review of Pharmacology and Toxicology. 2004. 44: 499-523.

[9] Carrel L, Willard HF. X-inactivation profile reveals extensive variability in X-linked gene expression in females. Nature. 2005;434(7031):400_4.

[10] Libert C, Dejager L, Pinheiro I. The X chromosome in immune functions: when a chromosome makes the difference. Nat Rev Immunol. 2010;10(8): 594_604.

[11] Klein SL, Marriott I, Fish EN. Sex-based differences in immune function and responses to vaccination. Trans Roy Soc Trop Med Hyg. 2015;109(1):9_15.

[12] Barber TJ, Geretti AM, Anderson J, Schwenk A, Phillips AN, Bansi L, et al. Outcomes in the first year after initiation of first-line HAART among heterosexual men and women in the UK CHIC Study. Antivir Ther. 2011;16(6):805_14.

[13] Murri R, Lepri AC, Phillips AN, Girardi E, Nasti G, Ferrara S, et al. Access to antiretroviral treatment, incidence of sustained therapy interruptions, and risk of clinical events according to sex: evidence from the I.Co.N.A. Study. J Acquir Immune Defic Syndr. 2003;34(2):184_90.

[14] Currier J, Averitt Bridge D, Hagins D, Zorrilla CD, Feinberg J, Ryan R, et al. Sex-based outcomes of darunavir-ritonavir therapy: a single-group trial. Ann Intern Med. 2010;153(6):349_57.

[15] Gandhi M, Aweeka F, Greenblatt RM, Blaschke TF. Sex differences in pharmacokinetics and pharmacodynamics. Annu Rev Pharmacol Toxicol. 2004; 44:499_523.

[16] Gianella S, Tsibris A, Barr L, Godfrey C. Barriers to a cure for HIV in women. Journal of the International AIDS Society: February 2016. Volume 19(1):20706.

[17] Addo M and Altfeld M. Sex-Based Differences in HIV Type 1 Pathogenesis. J Infect Dis. 2014 Jul 15; 209(Suppl 3): S86–S92

[18] Ho YC, Shan L, Hosmane NN, Wang J, Laskey SB, Rosenbloom DI, et al. Replication-competent noninduced proviruses in the latent reservoir increase barrier to HIV-1 cure. Cell. 2013;155(3):540_51.

[19] Data on file. ViiV Healthcare. July 2016