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Principles for selection of medicines. Dr Mary R. Couper Quality Assurance and Safety of Medicines WHO. Learning Objectives. The participants will learn the general principles for selection of medicines The participants will learn about the HIV medicines used in the WHO treatment guidelines
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Principles for selection of medicines Dr Mary R. Couper Quality Assurance and Safety of Medicines WHO
Learning Objectives • The participants will learn the general principles for selection of medicines • The participants will learn about the HIV medicines used in the WHO treatment guidelines • The participants will learn major toxicities of ARVs
Criteria for product selection • Prevalence of disease • Goals of treatment • Evidence of quality, efficacy and safety • Cost-effectiveness • Availability of products in the country
Criteria for selection (cont.) • Special groups needing treatment • Stability in certain conditions • Need for special diagnostic or treatment facilities • Training and experience of available personnel
Criteria for selection (cont.) • Fixed dose combination should be selected only when the combination has a proven advantage over single compounds • Important to use international nonproprietary names (INNs) instead of brand names
Prevalence (cont.) • An estimated 6.4 million people are living with HIV/AIDS in South-East Asia in 2004; it is the second highest number of cases in the world after sub-Saharan Africa and is increasing rapidly. • In WPRO an estimated 1.135 million people are HIV-infected
Goals in HIV/AIDS Treatment • Improved quality of life with effects for the individual, the family and the society • Reduction of HIV related morbidity and mortality • Restoration and preservation of immunology functions • Maximal and durable suppression of viral replication • Reduced need for medical intervention and support • Prevention/reduction of drug resistant strains of HIV and OI’s
Efficacy, Quality and Safety • Efficacy • WHO Model List of Essential Medicines • Quality • WHO prequalification scheme • Safety • WHO Model List of Essential Medicines
Cost-Effectiveness and Availability • When assessing cost-effectiveness, the cost of the total treatment, not just the unit cost of the medicines must be considered • The medicine must be available in the country
Special Populations • Adults and adolescents • Pregnant women or women of child-bearing age • Children • People with TB & HIV Co-infection • Health and emergency workers after occupational exposure • Victims of sexual assault
Other factors influencing selection • Adequate social support and patient care taker available • Adequate food supplies • Adequate health facilities nearby • Appropriate education for the patient re: adherence and side effect issues • Adequate testing and monitoring available
Antiretrovirals on WHO’s Model List of Essential Medicines • Nucleoside reverse transcript inhibitors • abacavir (ABC) • didanosine (ddl) • lamivudine (3TC) • stavudine (d4T) • zidovudine (ZDV or AZT)
Antiretrovirals on WHO’s Model List of Essential Medicines • Non-nucleoside reverse transcriptase inhibitors • efavirenz (EFV or EFZ) • nevirapine (NVP)
Antiretrovirals on WHO’s Model List of Essential Medicines (cont.) • Protease inhibitors • indinavir (IDV) • lopinavir + ritonavir (LPV/r) • nelfinavir (NFV) • ritonavir ( r ) • saquinavir (SQV)
Considerations that informed the choice of First-Line ARV Regimens • Potency • Side effect profile • Laboratory monitoring requirements • Potential for maintenance of future options • Predicted adherence • Coexistent medical conditions • Pregnancy or risk thereof • Concomitant medications (drug interactions) • Potential for infections with resistant viral strain • Cost and availability
First-Line Regimen Second-Line Regimen stavudine (d4T) or zidovudine (ZDV abacavir (ABC) Plus Plus lamivudine (3TC) didanosine (ddI) Plus Plus nevirapine (NVP) or efavirenz (EFZ) protease inhibitor: lopinavir + ritonavir (LPV/r) or saquinavir +ritonavir (SQV/r) * WHO Recommended First and Second-Line ARV Regimens for HIV Treatment in Adults/Adolescents * NFV in places without cold chain
First-Line Regimen Second-LineRegimen stavudine (d4T) or zidovudine (ZDV) abacavir (ABC) Plus Plus lamivudine (3TC) didanosine (ddi) Plus Plus nevirapine (NVP) or efavirenz (EFZ) Protease inhibitor: lopinavir + ritonavir (LPV/r) or nelfinavir (NFV), or saquinavir+ ritonavir (SQV/r) if wt >25 kg WHO Recommended First and Second-Line ARV Regimens for Treatment in Children
SIMPLIFIED GUIDELINES FOR ARV TREATMENT (HIV-1 INFECTION) If severe anemia If severe CNS symptoms or pregnancy Substitute ZDV to d4T 1st Line Regimen ZDV/3TC + EFV Substitute EFV to NVP If hepatitis or severe rash If severe anemia and neuropathy or pancreatitis Therapeutic Failure Substitute EFV to NFV Substitute ZDV to ddI (or ABC) If severe dislipidemia 2nd Line Regimen TDF + ddI + LPV/r If renal failure SubstituteLPV/r to NFV (or ATV/r) Substitute TDF to ABC TB/HIV If severe GI intolerance Substitute LPV/r to SQV/r DISTRICT/REGIONAL LEVEL LOCAL LEVEL Substitute ddI to ABC
Factors influencing change • Toxicity • Treatment failure
HIV Clinic 2005 Prescription Dr A. Who 31 December 2005 Re: Mr Joseph Bloggs R/ 1)abacavir + lamivudine + zidovudine 1 BD 2)atenolol 100 mg/d 3)acetylsalicylic acid 150mg/d 4)simvastatin 10 mg/d 5) bezafibrate 200 mg/d 6) metformin 500 mg/d 7) fluoxetine 50 mg/d 8) sildenafil
Common side effects and HAART… • Diabetes • Hypertension • Raised cholesterol, decreased HDL, raised LDL • Endothelial dysfunction • Lipodystrophy, with increased intra-abdominal fat
Non Nucleoside Reverse Transcriptase Inhibitors • Nevirapine and Efavirenz - Rash • Common - up to 20% • Stevens Johnson Syndrome • Liver Toxicity : up to 20% of pts on NVP, 2x higher in females, can be fatal. LFTs must be done • Rash • Neuropsychiatric
Nucleoside Reverse Transcripatse Inhibitors • Marrow suppression, particularly zidovudine • Neuropathy, particularly stavudine • Pancreatitis, particularly didanosine • Lactic acidosis, particularly stavudine • Myopathy, particularly zidovudine
Protease Inhibitors • Lipodystrophy • Fat redistribution • Raised triglycerides and cholesterol • Elevated blood sugar • Metabolic disorders • Nephrolithiasis (Indinavir >30%) • Hepatic disorders