An Update on the CHARM Rectal Microbicide Program IRMA Teleconference June 21 st , 2012 Ian McGowan MD PhD University of Pittsburgh

Microbicides are products that can be applied to the vaginal or

rectal

mucosa with the intent of preventing or significantly reducing the risk of acquiring STIs including HIV

N-9 Effect on Rectal Epithelium Baseline + 15 minutes + 15 minutes + 2 hours + 2 hours Phillips D et al. Contraception 2004 + 8 hours

Osmolality & Mucosal Integrity

Iso-osmolar Hyperosmolar

Fuchs E et al. J Infect Dis 2007

Gastrointestinal Adverse Events GI Adverse Events in the Tenofovir Arm RMP-02/MTN-006 (N = 12) Original Formulation N % Abdominal pain Rectal urgency Bloating Nausea Diarrhea Flatulence Proctalgia Other

Total

6 5 5 4 7 3 0 5 12 50% 42% 42% 33% 58% 25% 0% 42% 100%

Gastrointestinal Adverse Events GI Adverse Events in the Tenofovir Arm RMP-02/MTN-006 (N = 12) Original Formulation N % MTN-007 (N = 16) RG Formulation N % Abdominal pain Rectal urgency Bloating Nausea Diarrhea Flatulence Proctalgia Other

Total

6 5 5 4 7 3 0 5 12 50% 42% 42% 33% 58% 25% 0% 42% 100% 3 0 0 0 1 6 1 4 9 16% 0% 0% 0% 6% 38% 6% 25% 56%

Combination Rectal Microbicides Viral inhibition (%) Herrera C et al. AIDS 2011 (MDP IPCP PI: Peter Anton)

Conclusion • We need a rectal specific combination antiretroviral microbicide…..

CHARM Program • C ombination H IV A ntiretroviral R ectal M icrobicide Program • NIAID/DAIDS Integrated Preclinical Clinical Program • Consortium – University of Pittsburgh – UCLA – Johns Hopkins – UNC – CONRAD / Gilead McGowan I: IPCP U19 AI082637 / September 2009

CHARM Program Overview • Development of rectal specific antiretroviral microbicides • PK/PD evaluation in humanized mouse model • Pre-Phase 1 studies – Tenofovir – Maraviroc – Tenofovir & Maraviroc IPCP: U19 AI082637

Structure of the CHARM Program CHARM Steering Committee NIH IPCP Program IND Sponsors (CONRAD / IPM) Core A Administrative Core (University of Pittsburgh Core B Regulatory Compliance and Informatics (UCLA & CONRAD) Core C Formulation Development (University of Pittsburgh) Project 1 Nonclinical Strategies (University of Pittsburgh) Project 2 Topical ART to Prevent Rectal HIV (UNC ) Project 3 Exploratory Human Trials (UCLA)

Project 1 Nonclinical Strategies for Refining Combination Rectal Formulations Charlene S. Dezzutti, PhD

Project 1: Aims • To compare the utility of biopsy tissue versus resected tissue for evaluation of product safety.

• To evaluate rectal-specific TFV, GRFT, MVC and combination formulations for safety and efficacy.

• To evaluate the application time and the presence of semen on the efficacy of rectal specific formulations. • To evaluate combinations of candidate drugs (TFV, GRFT, MVC) and new classes of drugs for antagonism or synergy.

Updated 2012

Project 1: Update • Pre-clinical evaluation of new formulations: TFV/GRFT and TFV/MVC • Validation of JR-CSF & JR-CSF use in colorectal tissue.

K65R for • Incorporating the transmitter/founder (T/F) viruses for microbicide evaluation.

– pCH077.t/2627 (male) K65R and Y181C – pRHPA.c/2635 (female) wild type

TFV/GRFT/MVC • Tenofovir is a NRTI active at µM concentrations.

• Griffithsin is a potent homodimer protein active at nM concentrations.

– binds mannose-terminal Man 5–9 -GlcNAc 2 .

• Maraviroc is a potent CCR5 receptor antagonist active at nM concentrations.

TFV/MVC Evaluation in Explants

Test

TZM-bl cells Colorectal tissue 2 µM

TFV

~250 µM

MVC

24 nM ~10 µM Polarized colorectal explants 100-1000 fold N = 4 to 8 tissues N = 3 tissues

TFV/GRFT gel

Tenofovir Activity Against Resistant Virus

JR-CSF JR-CSF K65R

• • • The data suggest that clinical concentrations protect against DRV.

Lower drug concentrations (~100-fold) do not protect against DRV.

K65R confers ~2-fold benefit to the DRV.

Project 1: Next Steps • Continue the evaluation of TFV, GRFT, and MVC in explant studies – Wild type virus – Founder virus – Additional clades – Resistant virus • Add semen to explant model

Project 2 Topical Antiretrovirals to Prevent Rectal HIV Infection Victor Garcia-Martinez PhD

Project 2: Aims • Evaluate microbicide efficacy in a humanized mouse model and: – Determine the potential protective effect of (UC781) to prevent rectal HIV-1 infection – Determine the efficacy of topically administered tenofovir TFV to prevent rectal HIV-1 transmission.

– Determine the protective effect of a combination of TFV and (UC781) to prevent rectal HIV-1 transmission.

Project 2: Update • Tenofovir can protect humanized mice from rectal challenge with HIV-1 • Mice can be infected with human founder viruses • Resistant viruses can replicate in humanized mice but efficiency of infection is reduced by 75% • Gut commensal flora may impact whether mice can be infected with HIV

Topical Pre-Exposure Prophylaxis Rectal exposure with HIV-1 JR-CSF Peripheral Blood analysis for viral load and CD4 + T cell levels Tissue harvest Microbicide (PMPA) Weeks

Tenofovir Efficiently Prevents Rectal HIV Transmission

Rectal High Dose JRCSF 100 75

1% Tenofovir (n=12) Placebo (n=17) P value 0.0302

50 25 0 0 2 4 6 8 Time (Weeks Post Exposure) 10

M. Chateau

Tenofovir Prevents Rectal Transmission a Transmitted Founder Virus (THRO)

Rectal High Dose THRO 100

1% Tenofovir (n=6) Placebo (n=8)

75

P value 0.0223

50 25 0 0 1 2 3 4 5 Time (Weeks after exposure) 6 7

M. Chateau

How Efficiently are TFV Resistant Viruses Transmitted ?

TFV Resistant Mutant in Humanized Mice M. Chateau

Project 2: Next Steps • Continue to evaluate founder and resistant viruses in Hu-mouse model • Reconstitute germ free mice with commensal flora and evaluate impact on HIV infection • Determine whether maraviroc provides protection in the Hu-mouse model

Project 3 Exploratory Human Trials of Combination Rectal Microbicides Peter Anton MD

Project 3 Trial Sites • CHARM-01 – UCLA • Peter Anton MD – Pittsburgh • Ross Cranston MD • CHARM-02 – Johns Hopkins Medical School (JHU) • Craig Hendrix MD • CHARM-03 – UCLA, Pittsburgh, and JHU

Project 3: Aims • Cross site validation of mucosal assays – Flow cytometry – Explant infection • Phase 1 evaluation of tenofovir formulations: – Safety acceptability, PK/PD, distribution • Phase 1 evaluation of combination antiretroviral formulations: – Safety acceptability, PK/PD, distribution

Project 3: Update • Extensive cross-site validation studies have been conducted between UCLA and Pittsburgh – HVTN-MIG Program • CHARM-01 and CHARM-02 protocols completed and approved – Study initiation planned for Q3 2012 • Initial discussions on the design of CHARM-03

CHARM-01 • Phase 1 dose crossover comparison of current formulations of tenofovir 1% gel – Vaginal formulation – Reduced glycerin formulation – Rectal specific formulation • Endpoints – General and mucosal safety – PK/PD – Acceptability • Current status – Starting Q3 2012

CHARM-02 • Phase 1 single dose comparison of current formulations of tenofovir 1% gel with and without simulated RAI • Endpoints – Pharmacokinetics – Drug distribution using SPECT/CT imaging • Current status – Starting Q3 2012

Imaging Product Distribution Goldsmith J et al. Ann Stat App 2011

CHARM-03 • Phase 1 dose crossover evaluation of: – Placebo gel (RF) – 0.1% Maraviroc gel (RF) – 1.0% Maraviroc gel (RF) – Combination tenofovir 1% gel and 0.1% or 1.0% Maraviroc gel (RF) • Endpoints – General and mucosal safety – PK/PD • Current status – Starting Q3 2013

Project 3: Next Steps • CHARM-01 and CHARM-02 – Study initiation – Full enrollment and completion of visits – Data analysis • CHARM-03 – Develop and get approval for CHARM-03 protocol – Initiate and complete CHARM-03 study

Core C Formulation Development Lisa Rohan Pharm D

Core C: Aims • Develop a rectal specific microbicide product containing TFV • Develop a rectal specific combination microbicide containing TFV and alternative microbicide candidate (Griffithsin or Maraviroc) • Supply placebo formulations and formulated TFV, and a combination microbicide candidate.

• Development of biologically relevant product assessments for rectal microbicide products

Core C: Update • Rectal specific formulation of tenofovir 1% gel has been manufactured and will be used in CHARM-01 & CHARM-02 • Research grade formulations have been developed for explant evaluation • Stable rectal specific formulations of maraviroc have been made • Combination development is underway

Combination Gel Development Characterization:

Parameter

Drug content (% w/w) TFV MRV Viscosity @10rpm, 25°C(cps) Plastic viscosity*(cps) Yield stress* (D/cm 2 ) pH Osmolality (mmol/kg) Tenofovir Maravoric

Value

TFV/Non-micronized MRV TFV/Mircronized MRV 1.07

0.095

3743.69

755.65

1.04

0.099

3785.87

702.3

354.2

7 561 387.1

7 549

Core C: Next Steps • Stability assessments on all developed products. • Formulation development will be continued on the rectal TFV/MRV combination gel as well as the MRV alone gel. • Formulation of gels with higher maraviroc concentrations (> 0.5%) will be explored.

CHARM Program Summary

Summary • Novel rectal specific antiretroviral formulations have been developed and are being evaluated in explant systems • The Hu-mouse model has been optimized to evaluate microbicide efficacy • The first CHARM clinical studies with tenofovir will start in Q3 2012 • Clinical evaluations of maraviroc products will start in Q3 2013

General Rectal Microbicide Update • Project Gel – Rectal microbicide acceptability in young MSM – Stage 2 (Tenofovir Phase 1 study) open for enrollment • MTN-017 Phase 2 study moving towards Version 1.0

• Rectal satellite at AIDS 2012 – Sunday 22 nd July

Acknowledgements • NIH/NIAID/DAIDS – Integrated preclinical clinical program for HIV Topical Microbicides – 5U19AI082637