Last month's announcement that the Bill and Melinda Gates foundation will give up to $ 140 million to a Boston drug device manufacturer to develop an implantable mini-pump suite to provide pre-exposure prophylaxis (PrEP) drugs against HIV infection. HIV has focused attention on the future of PrEP. Is the future all about implants, or does it offer several options for people who want to use PrEP?
Implants and other long-acting delivery systems for drugs have attracted interest as a means of providing PrEP because studies consistently show that non-adherence - missing doses or do not use an intravaginal ring - is strongly correlated with the lack of PrEP protection. On the other hand, studies also show that people who maintain adequate levels of PrEP drugs are protected from HIV infection.
- 1.1 Several other research groups and companies have reported promising results from subdermal implants in animal trials, although Intarcia's implant technology appears to be the most advanced. Auritec, a company in Pasadena's autonomous ARV injection business, has received funding from the National Institutes of Health to test PrEP intravaginal injection rings, and has also been testing an implant containing tenofovir alafenamide (TAF) in dogs. The 40 day study showed that the implant was able to maintain 30 plasma concentration levels times higher than those needed to protect against HIV infection throughout the study period.
- 2 PrEP injection
- 3 vaginal rings
- 4 Contraception experiences highlight the value of multiple options
Intarcia is a company based in Boston Implantable development of mini-pump about the size of a toothpick also to inject a drug to control blood sugar in people with type 2. Product - ITCA Intarcia 650, which offers the drug exenatide to 2 type of diabetes - is already under review by the Food and Drug Administration of the United States after the successful phase III trials and might turn out to be licensed at the end of 2017 .
Last month Intarcia announced that it had secured a $ 50 million grant from the Bill and Melinda Gates foundation to develop its mini-injector technology to provide antiretroviral drugs to PrEP. More than $ 90 million will be donated to support access to the device in low- and middle-income countries and, if successful, a number of milestones could be reached. The pump's mini-Intarcia technology is an implant that is placed beneath the skin and dispenses a controlled amount of drugs every day. At this point Intarcia is not planning to use a particular antiretroviral product in its PrEP delivery system. Test development will seek to identify that the drug can be delivered at levels sufficient to prevent HIV infection.
Several other research groups and companies have reported promising results from subdermal implants in animal trials, although Intarcia's implant technology appears to be the most advanced. Auritec, a company in Pasadena's autonomous ARV injection business, has received funding from the National Institutes of Health to test PrEP intravaginal injection rings, and has also been testing an implant containing tenofovir alafenamide (TAF) in dogs. The 40 day study showed that the implant was able to maintain 30 plasma concentration levels times higher than those needed to protect against HIV infection throughout the study period.
30 Times !!!
PEPFAR of the President of the United States (Emergency Plan for AIDS Relief) also has supported research regarding a subcutaneous implant for delivery of TAF, developed by the University of California at San Francisco, which is still at an early stage of development. A larger research project, sustained long-term HIV protection (SLAP-HIV), a partnership based at Chicago Northwestern University and He received a financial support of $ 17 million guaranteed by the American Health Agency National Institutes of Health, is working to develop an implant that can provide any of these rogas: cabotegravir, rilpivirine, TAF or tenofovir tenofovir exalidex analogue (TXL, formerly CMX-157, Currently being developed for hepatitis B). The researchers also hope that their work will lead to the development of implants for antiretroviral therapy long-acting, eliminating the need of taking pills daily.
The development of injectable PrEP is more advanced than PrEP implants, and can provide a tentative measure of the form of implants that offer protection for up to one year. It can also provide short term protection for people who need long acting PrEP but who for whatever reason do not want an implant. Unlike implants, which can be detectable under the skin and therefore unacceptable to some people, an injection is invisible to others and does not need to be removed or replaced when the active drug is extinguished.
The disadvantage of injecting PrEP - and perhaps for breast implants - is that long-acting formulations were able to prolong AR drug levels.V at low levels in the body for a short period of months, exposing the risk of developing drug resistance if HIV infection occurs. [Translator's note: It has already appeared, and I have materials to translate and proofread newly infected for the first-line drugs are nonfunctional, burning an important stage of treatment that can last decades. I would say people who use PrEP do it consciously, using it as a secondary protective factor, NOT ABANDONING THE USE OF CONDOMS] The ÉCLAIR cabotegravir study of the injectable PrEP He found that nearly a quarter of participants still had levels of drugs that would probably be able to prevent HIV infection for a period of six months after their last injection, while 41% still had detectable sub-optimal levels at this point.
injectable PrEP is being tested at intervals of eight weeks by injection, requiring a high frequency of outpatient visits, which may not be suitable for all. [Editor's note: There is an article on this site that just says that the need for constant visits to clinics is counterproductive and you can read it here (Opens in new window)]
Intramuscular injections may also be unacceptable to some, although the user satisfaction ÉCLAIR (closing) of the study was high.
The development of injectable PrEP is focused on the use of two drugs, cabotegravir and rilpivirine, which are also being developed as nano injectable formulations of long-acting for treatment of HIV infections by the ViiV Healthcare.
A ViiV Healthcare is working on a long-acting injectable formulation of anti-retroviral therapy cabotegravir, which has recently entered a major phase III study in the United States, Latin America and Africa in men who have sex with men and trans women. The HPTN 083 study, sponsored by NIAID (National Institute of Allergy and Infectious
Diseases), has 4500 in its scope to receive a cabotegravir injection every 8 weeks or to take Truvada (tenofovir / emtricitabine) every day for an average of four and a half years. The results are expected in 2021 (the cure so vindicated for 2020 was already for the vinegar, despite the sensationalist video that led this response of the scientific community). The study companion, HPTN 084, Will begin testing injectable cabotegravir in young women in sub-Saharan Africa this year. Results of a phase II safety study (HPTN 077) are expected for early 2018 (increasingly distant from each much-touted cure for two thousand and twenty.
PATH is testing injectable rilpivirine in women under license from Janssen manufacturer, in a phase II safety study (HPTN 076). Taking place in the United States, South Africa and Zimbabwe. The results are expected in February 2017. Injections of rilpivirine are being given every eight weeks in this study.
vaginal rings containing dapivirine a ITRNN They have been tested in several phase III studies (ASPIRE and the RING study) and found to reduce the risk of infection by 65% in users consistent ASPIRE study. The rings were less effective in younger women due to less consistent use, indicating a need for more exciting action methods or less complicated for this particular population Translator's Note (...). The dapivirine ring is likely to undergo licensing review in 2018, and future developments will include experiences with rings containing other antiretroviral agents, including TAF and maraviroc, an HIV entry inhibitor. Multipurpose rings acting as contraceptive rings and HIV PrEP are also under development.
Contraception experiences highlight the value of multiple options
Although implants and injectables are able to become attractive to many people, they do not replace oral PrEP for those who need it. Some people may want to use PrEP only for a short time, or they may like the idea of an injection or an implant.
An overall analysis of contraceptive uptake has shown that widening the range of contraceptive options has increased total contraceptive use - With each new method widely available, total contraceptive users have increased contraceptive use by 4-8% between 1982 and 2009. Contraceptive studies suggest that a choice of method supports access and use.
Contraceptive studies in populations at risk for HIV infection show large variations in the type of contraception used from each country for each country, among the women participating in microbicide studies. For example, considering that predominated in Malawi, injectable contraception, oral contraception prevailed in Zimbabwe. These historical patterns are structured by the influence of the supplier and the health care provider over several decades and can influence the ways in which health services are beginning to offer different forms of PrEP. For example, greater experience with injectable or implantable contraception can lead to faster adoption of these modes when targeting women at higher risk of infection.
However, it is important to avoid assumptions about what kind of product is suitable for a specific population - this can act as a barrier to further use by other groups of people. For example, targeting a particular form of PrEP for sex workers may have the unintended effect of making other women reluctant to use it for fear of being identified as a sex worker (...).
Translated in 28 of January by Cláudio Souza of the original in: Implants and injectables: PrEP in the future. written by Keith Alcorn in 13 January 2017.
Even without review