For this to be a viable HIV reduction strategy, scale-up demand creation should be coordinated between all partners, the study authors said, and should be fast enough to build momentum and yield the expected results.
A reasonably-priced long-acting injectable cabotegravir could substantially reduce new HIV infection across low- and middle-income countries, according to a paper published in The Lancet HIV.
Investigators from South Africa created a model of economic evaluation and analysis in order to determine the incremental cost-effectiveness of long-acting injectable cabotegravir compared with tenofovir disoproxil fumarate and emtricitabine in South Africa. The study authors explained that long-acting injectable cabotegravir is taken every 2 months and is shown to be more effective at preventing HIV compared to daily oral tenofovir disoproxil fumarate and emtricitabine.
The study authors used data from two trials plus South African HIV epidemic models to create a high-risk and low-risk population over a 20-year period (2022 to 2041), which was then categorized by age, sex, sexual experience, sexual behavior, marital status, HIV testing history, and male circumcision status, the study authors said. They also noted the high-risk group was made up of 35 percent men and boys and 25 percent women and girls. The investigators assumed 85 percent and 65 percent tenofovir disoproxil fumarate and emtricitabine effectiveness for boys and young men, and girls, young women, and female sex workers, respectively.
With that in mind, the study authors determined that scenarios that included long-acting injectable cabotegravir avoided between 15 and 28 percent of new HIV infections compared to the baseline scenario.
When the model was analyzed with increased coverage with oral tenofovir disoproxil fumarate and emtricitabine, the study authors found an additional 4 to 8 percent of new HIV infections could be avoided compared to the baseline scenario.
If the long-acting drug cost was equal to the daily oral drug during the same 2-month period, the study authors learned that the incremental cost of the long-acting drug was higher than the daily drug (between 5 and 10 percent higher, compared to between 2 and 4 percent higher). They determined this was due to the higher assumed uptake of the long-acting drug, but the study authors wrote that the cost “would still be lower than the UNAIDS recommended 25 percent to be spent on prevention.”
The cost per dose estimate for the long-acting drug was between $9.03 and $14.47 if it would remain as cost-effective as the current treatment options ($4.70 per month). The cost of $9.03 represented the high coverage for the maximum duration while the amount of $14.47 represented the medium coverage for the minimum duration, the study authors explained.
“With a higher assumed uptake, the incremental cost of long-acting injectable cabotegravir to the HIV program is likely to be more than that of further scaling up tenofovir disoproxil fumarate and emtricitabine,” the study authors said.
To reduce the price, options include voluntary license agreements (which were recently agreed upon), a buy-down program, or a combination of these ideas, the study authors commented. But, they added, given that these factors depend availability for a large market, financial support and demand creation might be required to get this program up to the large scale that it requires.
“Although long-acting injectable cabotegravir has the potential to change HIV prevention, for large-scale implementation across low-income and middle-income countries, it first needs to be affordable, and lessons learned from oral PrEP programs show that scale-up and demand creation should be coordinated between all partners and should be fast enough to build momentum and yield results as high as those projected here,” the study authors concluded.