Epidemiological and economic impact of pre-exposure prophylaxis with targeted immunotherapies for COVID-19 among immunosuppressed patients in Argentina.

Background

Since Coronavirus Disease-19 (COVID-19) was declared a pandemic on March 11, 2020, more than 761 million cases were confirmed and almost 7 million deaths have been reported worldwide [ 1 ]. Additionally, intensive care admissions, hospital resources use, and productivity losses related to COVID-19 implied an increase in total costs with a detrimental effect on the economy worldwide [ 2 ]. For instance, it was estimated that the United States spent more than $160 billion in direct medical costs related to COVID-19 infection during the pandemic [ 2 ]. Also, in Argentina 133339 patients were admitted in intensive care units between February 2020 and June 2021, and by January 2023 there were 10032709 confirmed cases and 130,394 deaths [ 3 – 5 ].

Multiple interventions were applied to prevent the spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and prevent the development of severe outcomes of the disease. Among these interventions, vaccines are considered the most effective option to control the evolution of the pandemic by reducing the burden of COVID-19. Korang et al. showed in their living review that vaccines are effective in preventing COVID-19 as well as severe outcomes of the disease, including death [ 6 ].

However, Immunocompromised patients showed a substantially lower seroconversion rate after COVID-19 vaccination [ 7 ]. Agrawal et al. reported that after receiving full vaccination schedule plus a booster, immunosuppressed patients still had three to five times higher risk of hospitalization or death than immunocompetent patients [ 8 ]. Therefore, additional pre exposure prophylaxis (PeEP) would be important.

Different substances have been studied and shown no efficacy [ 9 , 10 ]. Targeted immunotherapy with monoclonal antibodies represents an option for preventing COVID-19 in the general population, especially in immunosuppressed patients. Tixagevimab–Cilgavimab is the unique targeted immunotherapy approved for pre-exposure prophylaxis against COVID-19. It is a combination of tixagevimab and cilgavimab, two monoclonal antibodies designed to bind to the SARS-CoV-2 spike protein at two sites. In February 2022 the Food and Drug Administration (FDA) authorized its use as pre-exposure prophylaxis against COVID-19 in adults and adolescents aged 12 years in a dose of 300 mg (150 mg for each component [ 11 ], and it was approved by the European Medicines Agency (EMA) on March 2022 [ 12 ]. However, multiple variants of SARS-CoV-2 have emerged due to mutations of the spike protein (with omicron variant and its sub-lineages being the greatest current dominance and consequent concern) which could reduce the neutralizing capacity of the monoclonal antibody, including tixagevimab–cilgavimab [ 13 – 15 ]. In this context, EMA issued a warning in December 2022 stating that monoclonal antibodies currently authorized for COVID-19 are unlikely to be effective against emerging (nonsusceptible) variants of SARS-CoV-2 [ 16 ]. Furthermore, in January 2023, the FDA revised the first authorization of tixagevimab–cilgavimab as pre-exposure prophylaxis in adults and adolescents 12 years of age and older that are moderately to severely immunocompromised [ 17 ]. After the revision, the FDA indicated its use only when the combined frequency of nonsusceptible variants nationally is less than or equal to 90%, based on available information, including variant susceptibility to tixagevimab–cilgavimab and national variant frequencies [ 18 , 19 ]. In Argentina, the National Administration of Medicines, Food and Medical Technology (ANMAT) did not yet authorize its commercialization.

Levin et al. published in June 2022 the results of the PROVENT trial, a phase 3 randomized, double-blind, placebo-controlled study of efficacy and safety of tixagevimab–cilgavimab in preventing symptomatic COVID-19 infection in adults aged ≥60 years or with a chronic medical condition or at increased risk of COVID-19 who are unvaccinated and not previously infected with SARS-CoV-2 [ 20 ]. At six months, tixagevimab–cilgavimab showed a relative risk reduction of 82.8% in the incidence of symptomatic COVID-19, compared to the placebo group, and the time until the development of symptomatic disease was longer in the treatment group (Hazard Ratio 0.17; 95% CI: 0.08 to 0.33) [ 21 ]. Some months later, Najjar-Debbiny et al. published the results of a retrospective cohort study that examined the real-life effectiveness of tixagevimab–cilgavimab in preventing SARS-CoV-2 infection and COVID-19–related hospitalization in immunocompromised patients in the era of Omicron [ 22 ]. A total of 732 patients who had at least one comorbidity or condition causing severe immunosuppression received 300 mg total of tixagevimab-cilgavimab. The incidence rate of SARS-CoV-2 infection was 4.18 in the tixagevimab–cilgavimab group and 5.64 per 100 person months in the control group. The hazard ratios were 0.75 for SARS-CoV-2 disease and 0.41 for COVID-19–related hospitalization in the tixagevimab–cilgavimab group compared to the control group [ 22 ].

Finally, in terms of cost-effectiveness, Sutton et al. recently reported findings for an analysis of tixagevimab-cilgavimab conducted for the United Kingdom (UK). The time horizon was one year for infection risk and a lifetime for patient outcomes. They concluded that tixagevimab–cilgavimab significantly reduces COVID-19 risk and cost burden in the immunocompromised population and is cost-effective at a willingness-to-pay threshold of £30,000 per QALY [ 23 ]. Also, Rattanavipapong et al. published recently their results of a cost-utility analysis that estimated the expected costs and health gains associated with the use of AZD5156 (a combination of cilgavimab and a long-acting monoclonal antibody AZD3152) and COVID-19 vaccines versus COVID-19 vaccines alone for the preexposure prophylaxis for COVID-19 among those who are at an increased risk of severe illness or death due to COVID-19 [ 24 ]. The authors concluded that considering a cost-effectiveness threshold of 160,000 Thai Baht (THB) per quality-adjusted life year (QALY) gained (1 USD = 36 THB in 2022), the only scenario found to be cost-effective was that of dialysis patients with inadequate immune response, with an incremental cost-effectiveness ratio (ICER) of 54,700 THB per QALY gained.

Despite the underlying controversy of tixagevimab–cilgavimab efficacy in the era of new COVID-19 variants and the fact that this therapy has not yet approved for its commercialization in Argentina, it remains relevant to characterize the potential target population amenable to this or other similar therapy’s in Argentina and the short-term economic implications associated with pre-exposure prophylaxis with targeted immunotherapies. In many low- and middle-income countries, formal health technology assessment processes are lacking. As a result, coverage and reimbursement decisions for high-cost technologies are often made under conditions of clinical and regulatory uncertainty, and sometimes in the absence of complete cost-effectiveness evidence. In this context, estimating the size of the eligible population and the potential budgetary impact of introducing such interventions represents a necessary first step for health system planning, independent of whether the intervention is ultimately adopted. Moreover, even when interventions are found to be cost-effective in specific subgroups, their implementation may be constrained by limited healthcare budgets. Therefore, budget impact analyses provide complementary information to cost-effectiveness studies by informing decision-makers about affordability, financial feasibility, and potential resource allocation challenges, particularly for vulnerable populations such as immunosuppressed patients. Thus, the objectives of this study were: 1) to identify those immunosuppressed conditions that could potentially benefit with the use of targeted immunotherapy as prophylaxis against COVID-19, 2) to estimate the size of patients that could be eligible for this indication in Argentina, 3) to estimate direct medical costs associated with pre-exposure prophylaxis and COVID-19 management, and finally, 4) to explore the short-term economic impact of introducing targeted immunotherapy for pre-exposure prophylaxis under different uptake scenarios, from the social security healthcare sector in Argentina.

Methods and data

Target population estimation

We used a four-step approach to estimate the number of immunocompromised adult patients ( > 18 years) who would be appropriate candidates for pre-exposure prophylaxis against COVID-19 with targeted immunotherapy in Argentina, using data from an exhaustive literature review and administrative databases. Figure 1 describes the four-step approach framework used.

We first identified immunosuppressive disorders that present a greater risk of severe outcomes secondary to COVID-19 infection. To do so, as a proxy, we tracked those conditions for which booster doses of the COVID-19 vaccine are recommended. In a second step, we reviewed the evidence for each immunocompromised disease identified in the first step and defined for which of those there is sufficient evidence of a significant reduction in the efficacy of the vaccine against COVID-19 compared to the immunocompetent population after a booster dose (third or fourth dose). In the third step, we estimated the total number of patients in Argentina with a diagnosis of each immunosuppressed condition prioritized in the second step. Finally (fourth step), since probably some patients with a medical diagnosis of the prioritized immunosuppression conditions would reach protection after receiving a COVID-19 booster (it would depend on individual clinical characteristics, different immunosuppressive levels for each of the conditions, among other variables), we estimate the proportion of the identified population that would receive a medical prescription with targeted immunotherapy (final target population).

Step 1 - identification of immunosuppressed conditions with a greater risk of severe COVID-19 outcomes

To identify immunocompromised conditions that present a greater risk of severe outcomes secondary to COVID-19 infection, we tracked those conditions for which booster doses of COVID-19 vaccine is recommended. So, we performed a review of guidelines or reports from public health centers, associations, or advisory groups with global impact. The guidelines or reports selected for this study were: the “Interim Clinical Considerations for Use of COVID-19 Vaccines” by The Centers for Disease Control and Prevention [ 25 ] and the “The Australian Technical Advisory Group of Immunization” [ 25 , 26 ].

We identified all conditions listed in such guides/reports. If a specific condition was better detailed in one guide or report than another, we extracted the more detailed condition.

Step 2 - prioritization of only those immunosuppressed conditions for which there is evidence of a significant efficacy reduction of the COVID-19 vaccines

An exhaustive literature review was carried out to evaluate the evidence of a significant efficacy reduction of the COVID-19 vaccine compared to the immunocompetent population after the initial or booster dose (third or fourth dose) for each of the immunosuppressive diseases identified in the first step.

We searched for information in PubMed on literature published until 1 of December 2022 (See Supplementary Material). We used a significant decrease in seroconversion after the initial scheme or booster dose compared to the immunocompetent population as an indirect proxy, in cases where data was unavailable on initial or booster vaccination efficacy.

Step 3 - estimating the total number of patients in Argentina with a medical diagnosis of the immunosuppressed conditions prioritized

Local databases were used to obtain the incidence or prevalence rate of the considered immunosuppressive conditions. The national information system of procurement and transplantation (SINTRA) [ 27 ] is the informatic system that administers, manages and audits procurement and transplant activity in Argentina. This system is coordinated and financed by the national institute of procurement and transplant in Argentina (known by its Spanish acronym INCUCAI). If there was no data in the INCUCAI database for specific conditions, prevalence or incidence data estimations for Argentina were taken from the Global Burden of Disease. In addition, in the event that there was no data for a specific condition either, information on prevalence or incidence rates was obtained from international literature and applied to local demography to estimate the number of subjects with that condition in Argentina.

Prevalence rate data were obtained for all conditions, except for those conditions in which immunocompromise was significant within the first year of diagnosis or active treatment. In those cases, the incidence rate was used. After applying the prevalence and incidence rates to the total number of adults in Argentina, the estimated absolute number of subjects diagnosed with any of the conditions included was obtained. The total number of Argentine adults was taken from the last census carried out in the year 2022 in that country [ 28 ].

Step 4- estimating the proportion of patients with a medical diagnosis of the immunosuppressed conditions prioritized that would receive a prescription for targeted immunotherapy

Since not all patients with a medical diagnosis of an immunosuppressed condition prioritized would present a significant reduction of the protection of COVID-19 vaccines, a percentage was applied for each condition to account for only those individuals who would be finally eligible by a medical doctor for a targeted immunotherapy. It was prioritized to obtain that percentage directly from the literature. In case it could not be obtained, it was used as a proxy for the seroconversion rate after vaccination for each prioritized condition. To do so, we obtained from the literature searches performed in step two, published information on the seroconversion rate after the booster (third or four doses) for each prioritized condition. In cases where there was no information on the seroconversion rate after a third or fourth dose (booster), the data on the seroconversion rate after the full vaccination schedule (two doses for most COVID-19 vaccines) was used. Given the controversy that the non-seroconversion rate could not be the best proxy for vaccination failure, these values were then validated by a local medical expert.

The target population was defined assuming a potential clinical benefit of pre-exposure prophylaxis, based on reduced vaccine response and consistency with populations included in available real-world effectiveness evidence.

Healthcare costs estimation

We estimated medical direct costs using a micro-costing approach from the social security healthcare sector in Argentina. In Argentina, social security sector is financed with contributions from workers and employers, provincial and national resources, and provides medical care to 26 million people (60% of the population) [ 29 , 30 ] We included the following medical direct costs categories: acquisition and administration costs of the targeted immunotherapy, outpatient and hospitalization costs due to COVID-19 [ 29 , 30 ]. All these costs were estimated in Argentine pesos and expressed in 2022 US dollars. The exchange rate was $130.8/USD1 was the mean of November of 2022 [ 31 ].

We used the case of tixagevimab–cilgavimab 600 mg every six months to estimate the costs related to the pre-exposure prophylaxis. To identify and quantify healthcare resources related to COVID-19, we used local clinical practice guidelines for managing patients with COVID-19, as recommended by the national health authorities, and consulted a local expert specializing in COVID-19 patient care. These sources provided a standardized approach to defining the base-case scenario. The unit costs were obtained from the Institute for Clinical Effectiveness and Health Policy (IECS) Unit Cost Database (UCD) [ 32 ].

Since the price of the targeted immunotherapy is not yet available for commercialization in Argentina, we used an estimated per-package cost provided by the pharmaceutical company that produces the medication. The estimated ex-factory price was $950 per tixagevimab-cilgavimab 600 mg package. For the administration costs, we considered the subcutaneous application cost by a registered nurse. Concerning adverse events costs related to immunotherapy, we decided only included them if a significant incidence ( > 3%) of an adverse event for tixagevimab–cilgavimab was reported, compared with the placebo arm in the pivotal clinical trial [ 21 ]. According to Squire et al. [ 33 ], the rates of the most commonly reported adverse events with tixagevimab–cilgavimab (headache: 6%, fatigue: 4%, and cough: 3%) were similar to those in the placebo group (rates of 5, 3, and 3%, respectively), so we decided to not include adverse event costs.

We included the outpatient and hospitalization costs related to the management of COVID 19. For the former, we considered one physician visit. We did not include antipyretics costs. To estimate hospitalization cost, we obtained data on the average number of hospitalization days in the general ward (no oxygen or low-flow oxygen therapy), intensive care unit (ICU) (with and without mechanical ventilation requirement) among immunosuppressed populations from Sheinson et al. [ 34 ]. The costs per hospitalization day were obtained from the IECSs UCD [ 32 ]. We assumed that patients would have no more than one COVID-19-related event per year.

Finally, we performed a literature review to explore the economic burden of each of the immunosuppressive disorders selected for this study, for illustrative purposes only (See supplementary material for more information).

Budget impact analysis

The budget impact analysis was conducted using tixagevimab–cilgavimab as a case study, given the availability of clinical effectiveness data and price information at the time of the analysis. We estimated the differential cost per year of the introduction of the therapy in the health system from the perspective of the security social sector. This perspective was chosen due to the significant coverage of the social security system in Argentina, which provides a representative framework for assessing access, costs, and the financial impact of new health interventions on a large segment of the population [ 35 ]. We estimated the net difference cost between the current scenario (without tixagevimab–cilgavimab) and the projected scenario (with a 100% inclusion of tixagevimab–cilgavimab). For that, we used the estimated target population and the direct medical costs in previous sections, the epidemiological and clinical parameters related to COVID-19 infection, and efficacy/effectiveness values of targeted immunotherapy (tixagevimab–cilgavimab 600 mg every six months).

The epidemiological and clinical parameters used to estimate the number of COVID-19 outpatients and hospitalized patients were: symptomatic infection risk over 12 months, the risk for hospitalization, distribution of hospitalized patients according to the severity of the disease. We also searched for the targeted immunotherapy efficacy/effectiveness value for a reduction in symptomatic infection and reduction in severity if symptomatic. The hazard ratio for reduction in disease severity was applied only to the transition from symptomatic infection to severe outcomes, defined as ICU admission with or without mechanical ventilation, and did not affect the probability of general ward hospitalization. Epidemiological parameters were primarily obtained from national databases. In the absence of local or regional data, the most recent evidence from peer-reviewed scientific literature was used. As a conservative assumption, long-term effects of COVID-19 were not included in the analysis.

Scenario analysis

Uncertainty was addressed through deterministic scenario analyses on key drivers of the budget impact, rather than formal probabilistic sensitivity analysis, due to limited availability of robust parameter ranges for several epidemiological and effectiveness inputs derived from real-world evidence. We performed scenario analyses to evaluate the impact of the uncertainty on the absolute number of patients with immunosuppressive disorders who will receive a prescription for targeted immunotherapy for pre-exposure prophylaxis against COVID-19. To that end, we conducted scenario analyses considering a 50% and a 25% tixagevimab–cilgavimab uptake instead of the 100% used in the base case analysis.

Results

Target population identification and estimation

The “Interim Clinical Considerations for Use of COVID-19 Vaccines” by The Centers for Disease Control and Prevention [ 25 ] and the “The Australian Technical Advisory Group of Immunization” [ 26 ], were the guidelines prioritized to identify the immunosuppressed conditions with a greater risk of severe COVID-19 outcomes. Table 1 details the diseases listed in these guidelines and our decision in favor or against the inclusion of them in the analysis with the corresponding rationale and respective bibliographic reference (results of the first and second steps).

Also, Table S1 details the prevalence and incidence rates for each condition included in the analysis along with the corresponding source (results of the third step, available at the Supplementary Material).

Finally, Table 2 reports the percentage of all eligible patients diagnosed with the immunocompromised conditions prioritized, who would be prescribed for pre-exposure prophylaxis with targeted immunotherapy against COVID-19, together with the rationale and the corresponding reference. Considering the total adult population of Argentina, we estimated that 12,788 patients would be prescribed with this therapy. This value represents a rate approximately 40–41 individuals per 100,000 adults.

Healthcare costs related

Table 3 presents the results of costs per patient-year. All costs were expressed in US dollars for 2022. The costs reported were used as direct inputs for the economic model and are expressed on a per–patient-year basis. Hospitalization resource use is reported in terms of bed-days. Costs are presented independently of associated probabilities, as probabilities are incorporated within the model structure and interact with cost inputs during model execution.

Budget impact analysis

Table 4 presents the key epidemiological, clinical, and efficacy/effectiveness parameters used to calculate the number of COVID-19 outpatients and hospitalized patients under 0 and 100% targeted immunotherapy uptake scenarios. The rest of parameters are detailed in the Table S2 in the Supplementary Material.

Table 5 shows the budget impact analysis for the case of tixagevimab–cilgavimab from the social security perspective in Argentina. The total net cost difference between the two scenarios (assuming 100 and 0% uptake of the targeted immunotherapy) was estimated at $24,254,732.3 in one year for the final target population ( n = 12,788). Consequently, there would be a net cost difference between both scenarios of $1,896.7 per patient year.

For the 100% uptake scenario, the targeted immunotherapy acquisition costs represented 99% of the total costs for this scenario. The 100% uptake scenario accounts for a total savings in a year of approximately $121,902.7 in outpatient and hospitalization COVID-19 related costs.

We present results of scenario analysis considering a 50 and 25% tixagevimab–cilgavimab uptake from the social security perspective in Argentina. The total net cost difference between the 50% or 25 and 0% uptake scenario was estimated at $12,127,366 and $6,063,683 in one year for the final target population ( n = 12,788). The 50 and 25% uptake scenarios accounted for total annual savings in outpatient and hospitalization COVID-19-related costs of approximately $80,442 and $40,221, respectively.

Discussion

Our study presented epidemiological and economic information regarding pre-exposure prophylaxis against COVID-19 with targeted immunotherapy in patients with severe immunosuppression conditions. Through a four-step approach we prioritized and selected some severely immunosuppressed conditions that would be benefited with a targeted immunotherapy pre-exposure prophylaxis. Specifically, we estimated that, in the case of Argentina, approximately 12,800 adult patients (around 40–41 adults per 100,000) diagnosed with a severe immunosuppressive condition (for which there is evidence of less efficacy or seroconversion after a COVID-19 booster vaccination), may be prescribed a targeted immunotherapy as prophylaxis. Likewise, our study identified those key costs for the targeted immunotherapy prophylaxis (tixagevimab–cilgavimab, which is currently the unique targeted immunotherapy approved for commercialization), including its acquisition and administration costs. Our study also reported costs related to outpatient and hospitalized COVID-19 patients, including the costs avoided due to the eventual efficacy of the targeted immunotherapy. Finally, we identified the annual medical management costs of the severe immunosuppression conditions prioritized. Additionally, our study included a budget impact analysis that estimated the incremental cost of the eventual coverage of tixagevimab–cilgavimab targeted immunotherapy, assuming 100, 50 and 25% uptake. This estimated per-patient annual incremental cost represents, for some conditions, 10–15% of the total annual medical cost of the disease (for example, post-kidney transplantation, non-Hodgkin lymphoma), being much lower in the case of primary immunodeficiencies (see Supplementary Material, Table S4 ).

In March 2023, Rattanavipapong et al. [ 24 ] analyzed the cost-effectiveness and budget impact of tixagevimab–cilgavimab as a pre-exposure prophylaxis against COVID-19 in patients with organ transplants, autoimmune disorders, and those undergoing dialysis, from the perspective of the Thailand government. The authors included the costs of moderate and severe COVID-19 cases for each underlying disease, and the acquisition and administration cost of the therapy. The study found that tixagevimab–cilgavimab was deemed cost-effective for dialysis patients who did not have a sufficient immune response to the vaccine, based on a threshold of 160000 THB per QALY gained. The budget impact model that they conducted concluded that incorporating tixagevimab–cilgavimab as a prophylactic treatment for all the patient groups included in the analysis represent an incremental cost equivalent between 0.6 and 2% of Thailand’s total current health expenditure in 2021 [ 47 ] if giving coverage to only patients with low levels of protective immunity or the entire eligible population, respectively.

The target population selected in the study [ 24 ] included not only organ transplant patients, as we did, but also patients under renal dialysis as well as autoimmune diseases. However, we did not include patients under renal dialysis given that the evidence shows that the efficacy of vaccines is high [ 48 , 49 ]. Regarding the solid organ transplant population we included patients that received a transplant during the last year (incident cases) assuming that these patients receive a higher dose of immunosuppressive therapy in a short period of time, therefore considering them to be at a higher risk of no response to COVID-19 vaccines. This may explain the difference in the rate of the target population included in our study compared to Rattanavipapong et al. [ 24 ]. Finally, recent publications show that patients with immunosuppressive therapies for non-oncological conditions such as arthritis or other autoimmune diseases who received a complete vaccination scheme plus a booster achieved high seroconversion rates [ 50 , 51 ]. Nevertheless, results from patients receiving anti-cd20 therapy should be discretionary interpreted.

The immunosuppressive disorders selected in our analysis are in line with those included in the study conducted by Najjar-Debbiny et al. [ 22 ]. This study estimated the effectiveness of tixagevimab–cilgavimab in the Omicron era. Although they considered the same conditions as we did, they also included patients with active multiple myeloma and patients under chimeric antigen receptor T-cell therapy (CAR-T). We decided not to consider patients with active multiple myeloma in our analysis since there is some evidence of high vaccine effectiveness at 3 to 6 months in this population [ 52 ]. Finally, concerning patients under CAR-T, we decided not to include this population since this therapy is not yet available for commercialization in our country. Since the analysis population broadly coincides, we opted to use the effectiveness value published by Najjar-Debbiny et al. [ 22 ] for the cost analysis we conducted.

Our study also has some limitations. To estimate the number of the final target population (which considers the percentage out of all patients with a diagnosis of a condition that would be prescribed pre-exposure prophylaxis with targeted immunotherapy due to a significant reduction of the protection of COVID-19 vaccines), we used, in some cases, low seroconversion rates after COVID-19 vaccination as a proxy for a reduction in the protection against COVID-19. However, some authors state that it could be possible to infer vaccine efficacy against COVID-19 from serologic information after addressing potential limitations [ 53 ]. Additionally, our estimates of healthcare resource utilization rely on local clinical practice guidelines and expert opinion, which provide a standardized framework for the base-case scenario. However, actual resource use may vary, particularly in complex or severe cases, potentially leading to an underestimation of costs and resource utilization. Finally, the probability of hospitalization among symptomatic COVID-19 cases was assumed to be uniform across all immunocompromised conditions due to the lack of robust, condition-specific estimates. Given the clinical heterogeneity of these populations—particularly among primary immunodeficiencies—this assumption may not fully capture differences in disease severity and could lead to over- or underestimation of hospitalization-related costs.

This study provides relevant information for local and regional decision-makers to guide informed assessment of a potential coverage of pre-exposure prophylaxis with targeted immunotherapy among immunosuppressed populations. Our results could be used in favor of optimal resource allocation decisions in Argentina.

Conclusion

This study provides epidemiological and economic information that could be useful for decision-makers to assess the coverage of pre-exposure prophylaxis with targeted immunotherapy among immunosuppressed populations, in a low-middle-income country setting.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1

Acknowledgements

Not applicable.

Author contributions

FRC, and NE planned the study, developed and fine-tuned the methodology. FRC, RL, and CML obtained data. FRC and CML did the analyses. All authors contributed to the interpretation of the data. FRC, RL and CML drafted the manuscript. NE, FRC and FA critically reviewed the manuscript. All authors reviewed and approved the final version.

Funding

This study was funded by AstraZeneca. The funding body had no role in the design of the study and collection, analysis, and interpretation of data or in writing the manuscript.

Data availability

All data generated during this study are included in this published article [and its supplementary information files].

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Footnotes

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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Associated Data

Supplementary Materials

Supplementary Material 1

Data Availability Statement

All data generated during this study are included in this published article [and its supplementary information files].