Atripla Missed Dose: What to Do?
Atripla is an alternative regimen for HIV-1 patients who are just starting treatment. Since its approval in 2006, it became one of the most commonly used drugs to treat HIV. Being a single-tablet regimen (STR), containing three potent drugs in one pill, it boosts adherence due to lower pill burden and less cost compared to other antiretroviral therapies (ART). Dosing is also flexible with Atripla because missing a dose can still lead to adequate viral suppression.
Why you should not forget to take Atripla?
As with all antiretroviral medications, missing a dose can affect the success of your treatment. In order to fight human immunodeficiency virus, there should be adequate levels of the drug in your system. The medications included in your regimen keep your viral load from increasing. If you miss a dose, the drug levels in your body falls down and your viral load may increase. But the most problematic impact of poor adherence to antiretroviral meds is the development of drug resistance. If you develop resistance to Atripla, your treatment options will be limited.
While it is highly recommended to take your pills daily, 100% compliance may be difficult to achieve. If you are taking Atripla, missing a dose is not the end of the world. Atripla has a long half-life of 17 hours. The three drugs stay in your system more than 24 hours, so it’s not a big risk if you occasionally forget to take your meds. While it’s okay to miss a few doses in a month, it is never okay to habitually skip doses–unless your healthcare provider has given you the go signal. Low drug levels cannot stop the virus from replicating, and this process can trigger mutations. When the HIV in your system mutates, you may develop resistance, which means your current regimen won’t be effective in fighting the virus anymore. You have to switch to a new ART that doesn’t contain the drugs found in your current regimen.
How many is too many?
There is no official statement on the number of doses that can be missed while taking Atripla. It is a forgiving regimen, but the impact of incorrect dosing is not always predictable. It depends on how fast an individual can absorb the drug and the metabolic characteristics of each drug. But according to several studies, lower levels of adherence may not pose a big risk in viral suppression. In a 2008 study by Martin and colleagues, virologic failure was 2.5 times higher in patients with <90% adherence who were taking unboosted protease inhibitors (PI) than those who were taking boosted PIs and NNRTIs. Atripla contains two NRTIs (emtricitabine and tenofovir) and one NNRTI (efavirenz). In another study with 900 treatment-naïve participants, it has been found that poor outcomes were higher on the group taking unboosted PIs. Boosters enhance antiretroviral drugs so that they stay in the body longer. Researchers found that those with adherence level of 95% have a 60–70% probability of best outcome, while adherence levels of 80–90% resulted to a 35–41% reduced probability of best response.
Is there a maintenance dose for Atripla?
To date, the recommended dose for Atripla is still one tablet daily, with or without food. But it is not impossible to have a maintenance dosing for Atripla in the near future. In the recent A-TRI-WEEK study, researchers concluded that a three-day per week Atripla regimen is a feasible treatment for HIV. Sixty-one virologically suppressed adult patients were randomized to take a daily dose of Atripla or a reduced three days in a week dosage (Mondays, Wednesdays, and Fridays). At the end of the study, no patients in both arms exhibited treatment failure. The authors recommend a larger and well-powered clinical trial to confirm the results of the study. Even though Atripla is no longer a first-line treatment in first world countries, it is still widely prescribed in other parts of the world, especially in low-income nations. The reduced dosing will definitely influence adherence, mainly because of lower pill burden and more affordable monthly cost.
There are many ways to help improve medication adherence. Before starting treatment, you should inform your healthcare provider if you have issues that can make adherence difficult. Your doctor may suggest medication aids such as pill reminders, pillboxes, and medication diaries to help you remember to take your meds on time. Use free pill reminder apps such as Care4Today from Prezista, the makers of another HIV drug darunavir, to receive daily reminders on your phone. A Malaysian study revealed that mobile phone reminders and peer counseling are effective in improving treatment outcome and adherence among patients taking ART.