[Are all analogue combinations equal?]. / Son iguales todas las combinaciones de análogos?

The huge improvement in the therapeutic arsenal for HIV infection has led to HIV becoming a chronic disease. Like us, our patients are aging and their life expectancy is close to that of the general population. Consequently, we need safe, easily administered drugs with interactions that can be controlled and the least possible impact on highly prevalent comorbidities such as atherosclerosis or coinfection with hepatotropic viruses. Drugs should fit the patient's lifestyle without affecting quality of life and, above all, be free of effects leading to stigma, such as lipoatrophy, a major concern for most recently diagnosed patients. The choice of the two nucleoside analogue reverse transcriptase inhibitors used at the start of antiretroviral therapy should be based on careful evaluation of the abundant data accumulated on all these determining factors which are heralding a new era in the control of HIV infection. Thus, in this scenario, thymidine analogues have been relegated to alternative use. Fixeddose combinations of tenofovir and emtricitabine (TDF/FTC) or abacavir and lamivudine (ABC/3TC) are the backbone of choice when initiating antiretroviral therapy. Direct comparative data are still scarce but suggest similar virological efficacy, with highly preliminary data suggesting some disadvantages associated with the use of ABC/3TC. After excluding patients at risk of hypersensitivity to ABC, both combinations are well tolerated, but TDF/FTC is associated with a better lipid profile. Recent data from the Data Collection on Adverse Events of Anti-HIV drugs (DAD) study show an unexpected association of ABC with increased cardiovascular risk and thus more detailed studies are required.

[Cost of nucleoside analogue reverse transcriptase inhibitor-related toxicity in HIV-1-infected patients]. / Costes de la toxicidad asociada a los análogos de nucleósidos inhibidores de la transcriptasa inversa en pacientes con infección por el VIH-1.

OBJECTIVE: To estimate the impact of toxicity related to nucleoside analogue reverse transcriptase inhibitors (NRTI) on the total cost of medical care in HIV-1-infected patients. METHODS: . A pharmacoeconomic model was developed from the data obtained by a prospective, observational, multicenter study performed in Spain (Recover). The study patients had developed one NRTI-associated adverse event (AE) that justified discontinuation of treatment with the drug. All costs derived from NRTI-associated AEs in the HAART regimens of HIV-1-infected patients over a period of one year were assessed. The cost assessment (2005 values) included direct medical costs (drugs and AE management) and indirect costs (loss of productivity). The healthcare resources used in AE management were estimated by an expert panel of clinicians. RESULTS: The use and cost of resources rose with increasing severity of all the AE. The average total cost per patient was estimated to be 4012 euro, which included 1789 euro in drug costs (NRTI associated with therapy discontinuation due to AE), and 2223 euro in direct and indirect costs of AE management (45% and 55% of total cost, respectively). Seventy-three per cent of AE-associated costs per patient came from lipoatrophy (560 euro), lipodystropy (535 euro) and peripheral neuropathy (533 euro). CONCLUSION: Management of NRTI-related toxicities is more costly than NRTI acquisition and produces a significant increase in the overall healthcare expenditure for HIV-1-infected patients. This fact should be taken into account when designing the most efficient antiretroviral treatment strategies.

[Retrospective epidemiological study on the durability of the treatment of HIV infection or AIDS in Spain]. / Estudio epidemiológico retrospectivo sobre la duración del tratamiento de la infección por el virus de la inmunodeficiencia humana en España.

BACKGROUND AND OBJECTIVE: To know the durability of consecutive regimens of antiretroviral treatment is important to design a long-term therapy, but there is not much information about this subject. PATIENTS AND METHOD: Retrospective epidemiological study of a sample of 401 patients who began antiretroviral treatment between January 1997 and April 2000 at ten Spanish hospitals. The duration of each consecutive antiretroviral regimen was calculated and the reasons for modification and discontinuation were described. RESULTS: In the 3 years and 3 months covered by the study, 48.6% of the patients received more than one regimen of therapy. Seventy five of the initial prescribed combinations included protease inhibitors. Median duration of consecutive lines of therapy was decreasing: 560, 360, 330 and 202 days for the first, second, third and fourth regimens, respectively. The main reason to modification was intolerance or toxicity (46.2, 49.1 and 47.1% for the first, second and third modification). A fifth of changes was originated by difficulties to follow the therapy. Virological failure was the reason for modification in 21.8, 24.5 and 26.5% of first, second and third changes. CONCLUSIONS: Duration of consecutive antiretroviral regimens progressively decreases. Intolerance or drug toxicity were the main reasons conditioning the change of treatment.