Intensive Adherence Interventions Improve Virologic Response to Antiretroviral Therapy (ART) in Treatment Naïve Patients L.D. ESCH1,2, K. KLEM1,2, L. KUHMAN1,2, R.G. HEWITT1,2, G.D. MORSE1,2 1University at Buffalo, Buffalo, NY and 2Erie County Medical Center, Buffalo, NY Presented at the 14th International AIDS Conference,Barcelona, Spain, July 7-12, 2002 Poster MoPeB3301

abstract

Background: Despite use of potent antiretroviral therapy (ART), failure rates of initial regimens are reported as high as 50%. Adherence appears to be a strong predictor of durability of ART; however, virologic outcomes data evaluating the effect of adherence interventions are lacking. The impact of intense adherence interventions by a pharmacist on virologic response in naïve patients (pts) was evaluated.

Methods: This was a prospective, case-controlled study. All ART naïve pts were eligible for intervention (ADH); however, pts not offered the service by their provider and pts refusing to participate served as controls, receiving standard of care (SOC). An additional group of historic controls were included for comparison. ADH pts were assessed for readiness and educated with an individualized, 3 module program focusing on basic understanding of HIV, psychosocial factors, and proper administration. Potential adherence barriers, anticipated toxicities, pill burdens, dosing intervals and regimen preferences were discussed with each pt, evaluated, reported to their provider and used to select an individualized ART. Pts were given tools such as pillboxes, daily dosing schedule, and beepers, if needed. We provided intensive coaching for the first 16 wks and had a phone line dedicated to these pts. Adherence (self-report), side effects and VL were addressed at each visit (wks 2, 4, 8, 16, 24). Demographics and VL were compared to SOC pts.

Results: 63 pts with similar demographics (n=25 ADH; 38 SOC) were evaluated for 48 wks. Median baseline VL (log10) is 5.31 c/mL (3.06-5.88, ADH) vs 5.24 c/mL (4.00-5.88, SOC). At wk 16, 84% vs 37% had VL<400, for ADH and SOC, respectively (p<0.001). Of pts with wk 48 follow-up (17 ADH, 19 SOC), 94% in ADH remained <400 vs 63% in SOC.

Conclusion: Tailored ART regimens and intensive adherence interventions are associated with enhanced virologic response out to 48 wks compared to SOC in ART naïve pts.

introduction

• Despite use of highly active antiretroviral therapy, failure rates of initial regimens have been reported to be as high as 50%.
• Adherence appears to be a strong predictor of virologic response and durability of HAART.
• The initial regimen has the greatest chance of suppressing viral load and determining disease outcome.
• Care should be exercised in determining who should begin therapy and at what point they are ready.
• Few studies have evaluated the impact of structured adherence interventions on virologic out comes in patients on potient antiretroviral therapy.
• The primary objective of this study was to evaluate the impact of intensive adherence interventions by a pharmacist on adherence to antiretroviral therapy and virologic response in naïve patients.

methods

This was a prospective, case-controlled study. All ART naïve patients were eligible for the intervention (ADH); however, those not offered the service by their provider and those refusing to participate served as controls, receiving only standard of care (SOC). An additional group of matched historic controls were included for comparison.

ADH patients were assessed for readiness and educated with an individualized, 3 module educational program focussing on basic understanding of HIV infection, psychosocial factors, and proper administration instructions. Potential adherence barriers, anticipated toxicities, pill burdens, dosing intervals and regimen preferences were discussed in detail with each patient, evaluated, reported to their provider, and used to select an individualized ART.

Patients were given tools such as pill boxes, dose cards, daily dosing schedule, and beepers, if needed. We provided intensive coaching for the first 16 wks and had a phone line dedicated to these patients for questions. Adherence (self-report), side effects and VL were evaluated and addressed at each visit (wks 2, 4 , 8 ,16, 24). Demographics and VL were compared to a cohort of patients who did not receive the intervention (SOC) using Chi-squared. Continuous variables were compared using the Kolmogorov-Smirnov Two Sample Test. All analyses were intention-to-treat.

d

results

63 patients (n=25 ADH; 38 SOC) with similar demographics were evaluated for 48 wks. There were no significant differences between baseline viral load (VL) or CD4 counts (Table 1).

At week 16, 84% vs 37% had VL<400, for ADH and SOC, respectively (p<0.001) and at 24 weeks 76% vs 37% had VL <400 c/mL (Table 2 ). Of those with 48 wk follow-up (17 ADH, 20 SOC), 94% in ADH remained <400, but only 60% in SOC.

Since ARV regimens were individualized in the intervention group, a comparison of regimens is illustrated in Table 3.

table 1 - Baseline demographic, virologic and immunologic factors between the Adherence Intervention and the Standard of Care control groups.

table 2 - Viral load responses at weeks 16 and 24 in the Adherence Intervention and the Standard of Care control groups.

table 3 - Comparison of the antiretroviral regimens used in the Adherence Intervention and Standard of Care groups.

discussion

In this study there was a lack of consistency among ARV regimens; therefore it is difficult to discriminate effect of intervention vs. individual regimens. However, it is possible that not standardizing the initial regimen aided in our intervention group’s success.

Those refusing Adherence Clinic may pre-select for individuals more likely to fail.

Our recommendation to defer starting therapy in those deemed not ready to begin, selects for those more likely to succeed and may account partly for our high success rate.

conclusions

Tailored antiretroviral regimens and intensive adherence interventions during the first 16 wks of therapy are associated with increased self-reported adherence and enhanced virologic responses compared to standard of care in antiretroviral naïve patients. These responses are sustained through 48 weeks.

Contact Information:

For more information, contact Dr. Lori Esch at 716-898-5742 or by email at lswick@acsu.buffalo.edu