The following tables summarize the aggregate results from the prospective, cross-sectional, voluntary testing population of unknown HIV status as well as those with known HIV-1 infection tested in POC and laboratory settings through June 30, 2004:

Table 1: POC INSTI™ results compared to PHL-based Abbott AxSym, n=3467

Abbott Axsym
	Positive	Negative
POC INSTI™ Positive	816	18
POC INSTI™ Negative	15	2448
POC INSTI™ Invalid	27	143

1 All were HIV antibody negative by confirmatory testing (combination of Western Blot, supplemental EIA, or p24Ag), i.e. INSTI™ false positive.
2 11/15 were negative by confirmatory testing, ie AxSym false positive. The remaining 4 were confirmed as HIV antibody positive, i.e. INSTI™ false negative.
3 All were Western Blot positive. Invalid INSTI™ results were not used for calculations of sensitivity and specificity.

Sensitivity of POC INSTI™: 99.5% (816/820, 95% CI: 98.8 - 99.8%); PPV: 97.8%
Specificity of POC INSTI™: 99.3% (2459/2477, 95% CI: 98.9 - 99.5%); NPV: 99.8%

Table 2: PHL INSTI™ on whole blood (EDTA) compared to PHL-based Abbott AxSym, n=3462

Abbott Axsym
	Positive	Negative
POC INSTI™ Positive	797	16
POC INSTI™ Negative	14	2620
POC INSTI™ Invalid	2	13

1 All were HIV antibody negative by confirmatory testing (combination of Western Blot, supplemental EIA, or p24Ag), i.e. INSTI™ false positive.
2 11/14 were negative by Western Blot ie. AxSym false positive. The remaining 3 were confirmed as HIV antibody positive, i.e. INSTI™ false negative.

Sensitivity of Blood INSTI™: 99.6% (797/800, 95% CI: 98.9 - 99.9%); PPV: 98.0%
Specificity of Blood INSTI™: 99.4% (2631/2647, 95% CI: 99.0 - 99.6%); NPV: 99.9%

Table 3: PHL INSTI™ on plasma compared to PHL-based Abbott AxSym, n=34622

Abbott Axsym
	Positive	Negative
POC INSTI™ Positive	798	2
POC INSTI™ Negative	14	2640
POC INSTI™ Invalid	1	7

1 All negative by Western Blot, i.e. INSTI™ false positive.
2 11/14 Western Blot negative (ie AxSym false positive), 3/14 Western Blot positive, i.e. INSTI™ false negative.

Sensitivity of Plasma INSTI™: 99.6% (798/801, 95% CI: 98.9 - 99.9%); PPV: 99.7%
Specificity of Plasma INSTI™: 99.9% (2651/2653, 95% CI: 99.7 - 100%); NPV: 99.9%

Table 4: PHL INSTI™ on serum compared to PHL-based Abbott AxSym, n=1384

Abbott Axsym
	Positive	Negative
POC INSTI™ Positive	361	1
POC INSTI™ Negative	3	1016
POC INSTI™ Invalid	0	3

1 negative by Western Blot, i.e. INSTI™ false positive.
2 All positive by Western Blot, i.e. INSTI™ false negative.

Sensitivity of Serum INSTI™: 99.2% (361/364, 95% CI: 97.6 - 99.7%); PPV: 100%
Specificity of Serum INSTI™: 99.9% (1016/1017, 95% CI: 99.4 - 100%); NPV: 99.7%

Seroconversion Panels
Relative sensitivity of INSTI™ compared to approved EIA methods for detection of antibodies in Commercial (BBI) Seroconversion Panels (n=25).

INSTI™ Performance	Number of Panels
Detected earliest bleed of panel	15
Within 1 bleed of earliest A positive	7
Within 2 bleeds of earliest A positive	1
Unknown	2

1 INSTI™ positive on panel samples collected 3 - 8 days following earliest EIA positive.
2 INSTI™ positive on panel sample collected 7 days after earliest EIA positive.
3 The last bleed in the panel was positive by at least 1 EIA, but negative by INSTI™.

HIV-2 Detection, n=49
All 49 frozen (-20C) serum samples were confirmed positive for HIV-2 antibodies by Western Blot (New Lav Blot HIV-2 (Biorad).
49/49 were positive with the INSTI™ HIV-1/HIV-2* rapid antibody test (100% sensitivity).
All INSTI™ and HIV-2 testing was conducted at the Laboratoire de Virologie, C.E.R.V.I., G.H. Pitie- Salpetriere, Paris, France.

Discussion and Conclusions

The INSTI™ HIV-1/HIV-2* rapid antibody test in POC settings as well as laboratory testing sites was equivalent to the Health Canada approved laboratory test of record (Abbott AxSym GO) in overall sensitivity, specificity, and early antibody detection. Performance characteristics of INSTI™ were highly concordant across matching finger-stick blood, venous whole blood (EDTA), plasma and serum. There was no INSTI™ lot-to-lot variation in performance observed. Work is continuing for HIV- 2 performance characteristics. Invalid results were more frequent at POC sites, and tended to be the result of sub-optimal amounts of blood collected with the disposable transfer pipette included in the kit. This is evidence that the INSTI™ test device will only work with the addition of adequate amounts of human IgG, providing a high degree of patients safety in validity of results.

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