The use of pharmacogenetics in clinical practice for the treatment of individuals with HIV infection in Thailand

Figures & data

Table 1 Demographic and baseline characteristics of 103 HIV-infected patients who performed pharmacogenetic testing

Variables
Median (range) age at time of diagnosis (years)	46 (20–85)
Sex, n (%)
Male	71 (68.9)
Female	32 (31.1)
At pharmacogenetic testing
Median (range) HIV RNA (copies/mL)	8,261 (19–2,670,000)
Undetectable (<40 copies/mL), n (%)	54 (52.4)
Detectable, n (%)	29 (28.2)
No data, n (%)	20 (19.4)
After pharmacogenetic testing
Median (range) HIV RNA (copies/mL)	39 (19–610,068)
Undetectable (<40 copies/mL), n (%)	76 (73.8)
Detectable, n (%)	17 (16.5)
No data, n (%)	10 (9.7)
At pharmacogenetic testing
Median (range) CD4 cell count (cells/mm^3)	329 (11–1,121)
≤200	25 (24.3)
201–350	31 (30.1)
351–500	23 (22.3)
>500	19 (18.4)
No data	5 (4.9)
After pharmacogenetic testing
Median (range) CD4 cell count (cells/mm^3)	404 (19–1,073)
≤200	13 (12.6)
201–350	18 (17.4)
351–500	33 (32.0)
>500	32 (31.1)
No data	7 (6.80)
Treatment status at the end of the study
Naive, n (%)	2 (2.0)
On antiretroviral therapy, n (%)	100 (97.1)
Tenofovir, lamivudine, efavirenz, n (%)	26 (25.2)
Tenofovir, emtricitabine, efavirenz, n (%)	22 (21.4)
Zidovudine, lamivudine, nevirapine, n (%)	7 (6.8)
No data, n (%)	1 (0.9)

Abbreviation: HIV, human immunodeficiency virus.

Table 2 Number and prevalence of HLA-B genotypes in 79 HIV-infected patients

	HLA-B*
	Normal	HLA-B*3505	HLA-B*5701	HLA-B*4001	Other HLA
Screening, n	7	0	0	2	13
Confirmation the cause of skin rash, n	0	1	2	1	2
ADRs besides rash, n	16	1	0	1	12
Choice of next ARV, n	8	0	2	1	10
Total, n	31	2	4	5	37
Prevalence (%)	39.2	2.5	5.1	6.3	46.8

Abbreviations: ADRs, adverse drug reactions; ARV, antiretroviral drug; HIV, human immunodeficiency virus; HLA-B*, human leukocyte antigen-B*.

Table 3 Prevalence of CYP2B6 predicted phenotypes in 51 HIV-infected patients

	CYP2B6
	Extensive metabolizer	Intermediate metabolizer	Slow metabolizer
Screening, n	11	17	1
Confirmation of the cause of skin rash, n	1	2	1
ADRs besides rash, n	6	7	3
Choice of next ARV, n	2	0	0
Total, n	20	26	5
Prevalence (%)	39.2	51.0	9.8

Abbreviations: ADRs, adverse drug reactions; ARV, antiretroviral drug; CYP2B6, cytochrome P 2B6; HIV, human immunodeficiency virus.

Table 4 Prevalence of CYP2B6 genotypes and predicted phenotypes in 51 HIV-infected patients stratified by the reasons of testing

Reasons and results	CYP2B6 polymorphisms
	No mutation	18492T>C	21563C>T	Other
Screening (n=38)
Extensive metabolizer, n	2	8	1	1
Intermediate metabolizer, n	3	12	3	1
Slow metabolizer, n	–	1	–	–
No CYP2B6, n	–	–	–	–
Confirmation of the cause of skin rash (n=6)
Extensive metabolizer, n	1	–	–	–
Intermediate metabolizer, n	1	–	–	1
Slow metabolizer, n	1	–	–	–
No CYP2B6, n	–	–	–	–
ADRs besides rash (n=39)
Extensive metabolizer, n	1	5	–	–
Intermediate metabolizer, n	1	5	2	1
Slow metabolizer, n	2	1	1	1
No CYP2B6, n	–	–	–	–
Choice of next ARV (n=20)
Extensive metabolizer, n	1	1	–	–
Intermediate metabolizer, n	–	–	–	–
Slow metabolizer, n	–	–	–	–
No CYP2B6, n	–	–	–	–
Total, n	13	33	7	5
Prevalence (%)	22.4	56.9	12.1	8.6

Note: Five patients had two mutations, and one patient had three mutations.

Abbreviations: ADRs, adverse drug reactions; ARV, antiretroviral drug; CYP2B6, cytochrome P 2B6; HIV, human immunodeficiency virus.