Gender-Specific Pharmacology
Within the concept of Gender-Specific Medicine, which aims to focus on the notions of both gender and sex—ultimately contributing to the development of personalized medicine in this regard—Gender-Specific Pharmacology plays a key role. Gender-Specific Pharmacology seeks to address the differences in the effectiveness and safety of various pharmacological treatments based on the sex and gender of the individual receiving care. These differences, in fact, have a significant impact on treatment efficacy and on the potential development of adverse side effects.
Key Terms in Gender-Specific Pharmacology
Sex: Assigned at birth, it refers to the biological characteristics of an individual, such as genetic, gonadal, anatomical, and hormonal traits.
Gender: A social construct that varies depending on the historical period, culture, and geographic area. This concept is fluid and changes over time, reflecting individual sensitivities.
Gender Binarism: Refers to the Western concept of gender, which recognizes only two categories: male and female. A non-binary view of gender includes more nuances beyond just male and female.
Cisgender: A person whose gender identity aligns with the sex assigned at birth.
Transgender: A person whose gender identity does not align with the sex assigned at birth. This term encompasses various gender identities.
AFAB: "Assigned Female At Birth", a person assigned female at birth.
AMAB: "Assigned Male At Birth", a person assigned male at birth.
The Issue of Underrepresentation in Clinical Trials
Studies on drugs begin with observing their effects on cells, then move to studies on animals, and finally on humans. However, these stages often do not consider sex differences in cell models, animals, or humans. Since 1993, there has been a law in the United States requiring studies funded by the National Institutes of Health to include both men and women, although there are still issues with inclusion percentages. However, there is no law mandating the inclusion of both male and female animals in preclinical studies. Historically, cisgender women have been underrepresented in clinical trials, making up only about 30% of the studied population, despite recent improvements.
This exclusion is paradoxical considering women’s higher life expectancy, which implies longer use of medications. According to ISTAT 2022 data, the average life expectancy for men is 80.1 years, while for women, it is 84.7 years. However, the healthy life expectancy is the same for both sexes, meaning women spend more time in a state of illness and, consequently, take medications for longer periods.
The reasons for this exclusion are historical: until the mid-1900s, it was believed that the female body was identical to the male body except for the reproductive system. Today, the difficulty in including women in studies is also due to economic needs and the simplification of experimental procedures. Women’s hormonal cycles and life phases, such as pregnancy, breastfeeding, and menopause, make studies more complex. Additionally, the use of hormonal contraceptives further complicates analysis.
Nonetheless, biological differences between the sexes affect drug absorption, metabolism, and elimination (ADME), processes that differ between men and women, particularly due to hormonal variations. Women, for example, tend to be more susceptible to side effects due to metabolic differences, but drug dosages are still based on a generalized male model of 70 kg.
Personalized medicine emphasizes the importance of considering differences between individuals in terms of ethnicity, age, sex, gender, weight, and body composition. On average, women weigh less than men and have a different body composition, with a higher percentage of body fat. This significantly impacts drug distribution, and dosages should be sex-specific.
Transgender People
Transgender individuals may choose to undergo gender-affirming hormone therapy (GAHT) with estrogen or testosterone, depending on the gender expression they desire. However, transgender people are often excluded from clinical trials, which focus mainly on HIV, HIV prevention (PrEP), and sexually transmitted diseases. This bias has led to a lack of knowledge about the effects and potential interactions between gender-affirming therapies and other medications.
The over half a million transgender individuals in Italy are not represented in drug study models. The lack of sex and gender-disaggregated data leads to increased risks, more side effects, and fewer rights being respected. The goal of gender-specific pharmacology is to tailor treatments to each individual’s needs, creating personalized medicine for men, women, and transgender people.
Progress Achieved
In recent decades, significant strides have been made:
In 1993, the U.S. Food and Drug Administration (FDA) mandated the inclusion of both sexes in all stages of drug development (FDA 1993–present).
In 2005, the European Medicines Agency (EMA) required the use of representative samples of both sexes in clinical trials ("Gender Consideration in the Conduct of Clinical Trials").
In 2016, the Italian Ministry of Health officially recognized gender as a determinant of health (see PDF).
In 2019, the Ministry of Health developed the Plan for the Implementation and Dissemination of Gender Medicine (see PDF).
On July 24, 2023, the plan adopted by Ministerial Decree (D.M.) of June 13, 2019, was formally implemented, with the approval of the regional programming document entitled "Regional Plan for the Application and Dissemination of Gender Medicine (2023–2025)."
The Italian National Health Service (SSN), the World Health Organization (WHO), and the United Nations (UN) have also promoted this new approach to medicine, encouraging the adoption of new preventive, diagnostic, and therapeutic strategies that take into account the differences between men and women—not only in biological and clinical terms but also in cultural and socio-psychological aspects (Gender as a Determinant of Health). This approach can also help the SSN achieve savings, including economic ones, by reducing the use of ineffective medications and lowering the risk of relapses and hospitalizations through more targeted treatments, ultimately improving public health.
Paying attention to sex and gender in public healthcare is therefore a strategic and effective choice.The 2018 Law No. 3 on the application of Gender Medicine (Plan for the Implementation and Dissemination of Gender Medicine), from which the 2019 Plan was derived, emphasizes the importance of ensuring prevention, diagnosis, and treatment for every individual with an approach that considers gender differences across all stages of life and in every living and working environment.
This vision aligns with the 2030 Agenda (UN - Italy’s New Agenda for Sustainable Development), particularly Goals 3 and 5 (Health and Well-being, and Gender Equality), and with the Global Health 50/50 initiative, a supranational organization aiming to promote greater equity in health by advocating for sex- and gender-disaggregated data.
Our Goals
Medicine should be guided by the principle of equity, providing everyone with the same opportunities, acknowledging the differences between individuals, and ensuring social justice for all. Our research, through the commitment of our Third Mission, aims to raise awareness about this issue and promote the development of an inclusive future medicine. Through our work, we want to emphasize that we should not just treat diseases but care for and about people.
Sources
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