Prescribed medicine

To tackle any disease it is not merely only diagnosing correctly and offering quality treatment but ensuring that the patients adhere to treatment that is of paramount importance. Timely and correct diagnosis and availability of standard, evidence-based and effective treatment cannot be of much help unless the patient takes the prescribed drugs for the complete duration of time. So over and above everything else it is the patients' willingness and determination to take their medicines regularly that can bring relief.

At the recently concluded 6th National Conference of AIDS Society of India (ASICON 2013), Dr K Satish, a senior Pulmonologist from Bangalore, stressed upon the importance of adherence to both care and medication for the success of any treatment programme including HIV/AIDS. He defined adherence as “the patient’s active participation in planning care and treatment and is based upon shared decision making between patient and provider. It is based upon understanding, consent and partnership in healthcare delivery between patient and provider.”

Dr Satish said that, “Adherence is a complicated issue regardless of the nature of the disease and is equally problematic in resource- poor and rich settings. Likewise non-adherence to antiretroviral therapy (ART) in treatment of HIV is common to all groups of individuals on treatment and is comparable to that in other chronic diseases like diabetes, hypertension and heart disease. Overall 40-60% of people taking ART are less than 90% adherent. But we need more than 90% adherence for successful outcomes of HIV treatment. ART has been found to fail in nearly half of the patients for whom it is prescribed mainly due to non-adherence. Then again association between poor-adherence and ARV resistance is well documented. Suboptimal adherence predisposes to drug resistance.”

Some of the factors listed by Dr Satish that affect adherence to a prescribed treatment regimen include patient-variables like sex, age, economic and literacy status; psychosocial factors like depression, alcohol and substance abuse, lack of perceived efficacy of ART, lack of social support and lack of knowledge; treatment regimen like complexity of the regimen (pill burden, dosing frequency, difficulty of administration, food instructions, side effects of medicines, cost and access to medicines); disease characteristics like stage of HIV infection, HIV-related symptoms and HIV-associated Opportunistic Infections (OIs); and above all patient-provider relationship like patient’s overall trust and satisfaction in the provider and provider’s willingness to include patient in treatment decisions.

He said, challenges of adherence to ART are further compounded as:

(i) it must be taken lifelong;

(ii) there are specific dietary and fluid instructions;

(iii) there could be short and long term side effects;

(iv) it requires near perfect adherence—more than 90%

(v) there was a high pill burden in the past; and

(vi) a lot of stigma is still associated with the disease.

He further explained to Citizen News Service (CNS): "Understanding these factors can increase providers’ attention to adherence. A team approach is needed to optimally maximize adherence. It should involve physicians, nurses, pharmacists, other healthcare providers and also family/friends of the patient. The team must ensure that the patient is committed to therapy before beginning ART. Adherence should also be monitored over time."

Researchers and pharmacists have helped by offering simplified treatment regimens that lead to better long term medication adherence, improve quality of life, avoid long term toxicities, and reduce risk of virologic failure. Earlier ART itself involved daily dose of multiple tablets. Then again, many HIV patients also have to take pills outside of ART to deal with other co morbidities and opportunistic infections to which they are predisposed because of their HIV, which adds on to their pill burden. Dr R Sajith Kumar of Kottayam informed that, “We now have the single tablet regimens under ART which are recommended by current HIV treatment guidelines as preferred options. All drugs in the regimen with comparable PK are combined in one pill to provide optimal efficiency. Regimen simplification advances patient care by way of better adherence, lower resistance development, higher persistency leading to long term success, less hospitalization and lower cost of care.”

He was happy that, “More than 10 ARV drugs/drug combinations are now approved for once daily administration in some countries. Currently 3 single tablet regimens have been approved by the FDA—tenofovir, emtricitabine and efavirenz (approved in 2006); tenofovir, emtricitabine and rilpivirine (in 2011); Quad—tenofovir, emtricitabine, elvitegravir and cobicistat (approved in 2012).

In terms of convenience co formulations of EFV/FTC/TDF or RPV/FTC/TDF allows for once daily dosing with a single tablet. In India Cipla has pioneered a three in one tablet Triomune containing a fixed dose combination (FDC) of three ARVs (lamivudine, stavudine and nevirapine).”

“As FDC and single tablet regimens reduce the pill burden and dosing frequency they are associated with higher adherence and increased patient satisfaction. There are improved health outcomes and reduced costs. According to one study, the use of once daily single tablet regimen was associated with a 17% reduction in total healthcare cost. Another study found that single tablet regimen is associated with 34% lower risk of hospitalization (which also means lower risk of acquiring hospital related infections), and patients who receive once daily single tablet regimens are 6 times more likely to adhere to therapy.”

But the flip side is that if the patient misses one tablet she/he misses all the drugs. Also patients who have difficulty in tolerating any of the drugs in the single tablet regimen/ FDC cannot switch to this single tablet treatment. Again, there is no way for doctors to adjust the doses of individual drugs within the regimen. So while FDC may work very well for many patients, some doctors find the lack of flexibility limiting, particularly when they try to manage toxicity and other side effects.