Safety, Immune, and Antiviral Effects of Pegylated Interferon Alpha 2b Administration in Antiretroviral Therapy-Suppressed Individuals: Results of Pilot Clinical Trial

Abstract

In the pilot NCT01935089 trial, we tested whether pegylated interferon alpha2b (Peg-IFN-α2b) with antiretroviral therapy (ART) was safe and could impact HIV and immune measures in blood and in gut-associated lymphoid tissue (GALT). Twenty HIV-1+ ART-suppressed individuals received 1 μg/kg/week Peg-IFN-α2b with ART for 20 weeks, with intermediate 4-week analytical ART interruption (ATI). Safety, immune activation, HIV viral load and integrated HIV DNA in blood, and HIV RNA and DNA in gut biopsies were measured. A total of 7/20 participants experienced grade 3-4 adverse events, while 17/20 participants completed the study. Of the 17 participants who completed the study, 8 remained suppressed during ATI, while all 17 were suppressed at end of treatment (EoT). As expected, treatment increased activation of T and natural killer (NK) cells and IFN-stimulated molecule expression on monocytes in periphery. While circulating CD4+ T cells showed a trend for a decrease in integrated HIV DNA, GALT showed a significant decrease in HIV-1 RNA+ cells as measured by in situ hybridization along with a reduction in total HIV DNA and cell-associated RNA by EoT. The observed decrease in HIV-1 RNA+ cells in GALT was positively associated with the decrease in activated NK cells and macrophages. This study documents for the first time that 20 weeks of immunotherapy with Peg-IFN-α2b+ART (inclusive of a 4-week ATI) is safe and results in an increase in blood and GALT immune activation and in a significant decrease in HIV-1 RNA+ cells in GALT in association with changes in innate cell activation.

Keywords: GALT; HIV DNA; HIV RNA; activation; antiretroviral therapy; pegylated IFN-α2b.

Conflict of interest statement

The authors declare that they do not have a commercial or other association that might pose a conflict of interest.

Figures

FIG. 1.

Study schema and disposition. (A) Schema of the trial visit and relative activities during the 12 visits scheduled to occur over 32 weeks. Treatment is represented by blue boxes (ART), green boxes (combined administration of ART and Peg-IFN-α2b), or orange boxes (ATI, Peg-IFN-α2b monotherapy). (B) CONSORT flow diagram of the study individual disposition. Red arrows in (A) indicate time points used for sample analysis (BL:ART; EoT: combined administration of ART and Peg-IFN-α2b). ART, antiretroviral therapy; ATI, analytical ART interruption; BL, baseline; CONSORT, consolidated standards of reporting trials; EoT, end of treatment; Peg-IFN-α2b, pegylated interferon alpha2b. Color images are available online.

FIG. 2.

Clinical measurements during follow-up. CD4+ T cells/mm3, CD4+ T cell percentage (%), log10 HIV-1 RNA copies/mL, and neutrophil cells/mm3 levels during follow-up for study participants. Color lines indicate each participant. As described in Fig. 1A, treatment is represented by blue boxes (ART), green boxes (combined administration of ART and Peg-IFN-α2b), or orange boxes (ATI, Peg-IFN-α2b monotherapy). Color images are available online.

FIG. 3.

Changes in immune variables in blood and in GALT after 20 weeks of combined administration of ART and Peg-IFN-α2b (inclusive of a 4-week ATI period). (A) CD3+CD4+ T cells/mm3 and CD3+CD4+ T cells percentage (%). (B) CD3+CD8+CD38+ % of CD8+ T cells, CD3+CD8+PD1+ % of CD8+ T cells, CD3+CD4+Tetherin+ % of CD4+ T cells, Lin3−CD56bright % of lymphocytes, MFI of CD38 on Lin3−CD56bright, MFI of NKG2A on Lin3−CD56bright, Lin3−CD56dimCD16+ % of lymphocytes, MFI of CD38 on Lin3−CD56dimCD16+, MFI of NKG2A on Lin3−CD56dimCD16+, CD14+BDCA2−BDCA4−CD169% of CD14+BDCA2−BDCA4−, MFI of Tetherin on CD14+BDCA2−BDCA4−, and CD163 pg/mL in periphery. (C) CD3+CD4+ T cells % of live cells, CD3+CD25+CD69+HLA-DR+CD4+ T cells % of live cells, CD3+CD4− T cells % of live cells, CD3+CD25+CD69+HLA-DR+CD4− T cells % of live cells, and MFI of PDL1 on CD3−CD68+CD33+ in GALT. Immune variables are shown at BL:ART and EoT (time points illustrated in Fig. 1A). Available data are shown for study participants together with significant p values. Statistics was performed with JMP Pro11 (SAS Institute, Cary, NC). Briefly, differences between BL and EoT were tested, using Wilcoxon Signed-Rank or paired t-tests depending on data distribution. GALT, gut-associated lymphoid tissue; MFI, mean fluorescence intensity; NK, natural killer; PD1, programmed cell death 1.

FIG. 4.

Changes in HIV DNA in blood and in GALT after 20 weeks of combined administration of ART and Peg-IFN-α2b (inclusive of a 4-week ATI period). (A) Log10 integrated HIV-1 DNA copies/106 CD3+CD4+ T cells in blood. Top panel shows available data for study participants during follow-up with color lines indicating each participant and treatment being represented by blue boxes (ART), green boxes (combined administration of ART and Peg-IFN-α2b), or orange boxes (ATI, Peg-IFN-α2b monotherapy). Bottom panel shows available data for study participants at BL and EoT together with the median and IQR and p values. (B) Log10 total HIV-1 DNA copies/106 cells in gut-associated lymphoid tissue (GALT). In all panels, time points shown are illustrated in Fig. 1A. (B) Shows available data for study participants at BL and EoT together with the median and IQR and p values. Statistics was performed with JMP Pro11 (SAS Institute). Briefly, differences between BL and EoT were tested, using Wilcoxon Signed-Rank or paired t-tests depending on data distribution. IQR, interquartile range. Color images are available online.

FIG. 5.

Changes in HIV-1 RNA in GALT after 20 weeks of combined administration of ART and Peg-IFN-α2b (inclusive of a 4-week ATI period). (A) 20 × rectal tissue montage for BL:ART and EoT for participant PIP-003 representing a merging of several gut-associated lymphoid tissue (GALT) sections hybridized with HIV-specific Sulfur-35 labeled antisense probes; a positive signal for HIV vRNA expression is shown as green dots under epipolar light microscope in magnified insert areas (red box inserts) with red arrows highlighting the vRNA HIV expression signal. (B) HIV-1 RNA+ cells/mm3 in GALT. In all panels, time points shown (BL, EoT) are illustrated in Fig. 1A. (B) Shows available data at BL and EoT with color lines indicating each participant and p value. Statistics was performed with JMP Pro11 (SAS Institute). Briefly, differences between BL and EoT were tested, using Wilcoxon Signed-Rank or paired t-tests depending on data distribution. Color images are available online.