. 2001 Apr;75(7):3291–3300. doi: 10.1128/JVI.75.7.3291-3300.2001

TABLE 1.

Clinical characteristics and amino acid mutations in PR and RT of resistant isolates^a

Isolate	Current treatment	Prior treatment	No. of CD4⁺ cells/μl	Viremia (log copies/ml)	Protein and mutation(s)	Comments
B495	d4T, ritonavir, saquinavir	AZT, ddC, ddI, indinavir	230	5.5	PR: M46I, V77I, I84V, L90M RT: M41L, L210W, T215Y CL: P453L	Long-term failure to achieve viral suppression and slow immunological deterioration
B497	d4T, ritonavir, saquinavir	AZT, 3TC, ddI, indinavir	411	5.2	PR: L10I, K20M, I54V, A71V, G73S, I84V, L90M RT: K65R, V75I, F77L, Y115F, F116Y, Q151M, K219Q CL: P453L	Clinical and immunological stability despite lack of viral suppression
B670	None	None	773	3.4	PR: L10I, A71T, V77I, V82A, L90M RT: M41L, E44D, D67N, M184V, L210W, T215A CL: WT	Horizontal multidrug-resistant-HIV-1 transmission

Amino acid substitutions conferring resistance to PR and RT inhibitors (16) and cleavage site adaptations in Gag (CL) (5) are given in the single-letter code. d4T, stavudine; AZT, zidovudine; ddC, dideoxycytosine; ddI, dideoxyinosine; 3TC, lamivudine.