ةي : لآا ةرقبلا ةروس

سورة البقرة: اآلية

HCV RELAPSERS AND NONRESPONDERS: How to deal with them? BY Prof. Mohamed Sharaf-Eldin Prof. of Hepatology and Gastroenterology Tanta University

Achieving SVR The ability to achieve a SVR is the result of 3 independent steps The patient must achieve a virologic response The patient must maintain the response The patient must not relapse To overcome nonresponse and relapse, the reasons for failure must be defined

Defining an Initial Virologic Response

HCV RNA (log 10 IU/mL) Chronic Hepatitis C:Defining an Initial Virologic Response 8 7 6 5 4 3 2 1 0 PegIFN/RBV Null response Partial response Breakthrough Weeks Relapse 2 log decline Limit of detection SVR 0 4 8 12 18 24 30 36 42 48 54 60 66 72 78

Patients (%) Frequency of Responses 100 80 60 66 Genotype 1 [1] Genotypes 2/3 [2] EVR = 80% 40 20 0 15 35 20 15 4 12 24 Week Undetectable HCV RNA Achieved 7 15 5 20 2 Partial Nonresponse Response 1. Ferenci P, et al. J Hepatol. 2005;43:425-433. 2. Shiffman ML, et al. N Engl J Med. 2007;357:124-134.

Medical Need in Chronic Hepatitis C Retreatment Is Growing Despite significant advances in HCV therapy, approximately half of genotypes 1 and 4 patients do not achieve SVR on initial treatment. First generation HCV oral direct antivirals are several years from approval 1. Manns M, et al. Lancet, 2001;358:958-965. 2. Fried M, et al. NEJM, 2002;347:975-982. 3. Poynard T, et al. AASLD, 2006; Abstract 1123.

Initial Approach to the Patient With Treatment Failure Review of records to assess status of previous response to therapy End-of-treatment HCV RNA level critically important Duration of previous treatment Degree of HCV RNA reduction as a result of previous therapy Determination of previous degree of compliance Which interferon alfa regimen was taken and at which dose? How many ribavirin tablets/day at starting dose? How many missed doses? How many dose reductions? May have to ask patients repeatedly to get accurate answers

Populations of Nonresponders IFN Monotherapy IFN and RBV PegIFN and RBV

Why Patients Fail HCV Therapy Noncompliance with physician recommendations Inherently resistant to IFN Response not recognized Adverse events Therapy stopped Dose of pegifn and/or RBV reduced Treatment not continued for a sufficient period of time

HCV RNA Positive (%) Treatment of Chronic Hepatitis C: Impact of Stopping RBV Those who stopped RBV at Wk 24 had higher breakthrough and relapse rates 50 40 30 Continue RBV (n = 173) Stop RBV (n = 176) 32 26 42 42 29 20 10 0 14 12 5 6 0 2 2 3 0 24 30 36 48 52 60 72 Weeks

Why Patients Fail HCV Therapy Noncompliance with physician recommendations Inherently resistant to IFN Response not recognized Adverse events Therapy stopped Dose of pegifn and/or RBV reduced Treatment not continued for a sufficient period of time

HCV RNA (log 10 IU/mL) The Null Response 8 PegIFN/RBV 7 6 5 4 2 log decline 3 2 1 Limit of detection 0 0 12 24 36 48 60 72 Weeks No significant decline in HCV RNA despite full-dose pegifn Occurs in 20% of patients Patients likely resistant to the effects of IFN Pattern more common in blacks May not be overcome by higher doses of pegifn?

Why Patients Fail HCV Therapy Noncompliance with physician recommendations Inherently resistant to IFN Response not recognized Adverse events Therapy stopped Dose of pegifn and/or RBV reduced Treatment not continued for a sufficient period of time

HCV RNA should be measured at monthly intervals until the patient either has undetectable HCV RNA or a nonresponse pattern has been defined and treatment is discontinued. Once undetectable, it is recommended that HCV RNA be monitored every 3 months until 24 weeks after treatment is discontinued

Why Patients Fail HCV Therapy Noncompliance with physician recommendations Inherently resistant to IFN Response not recognized Adverse events Therapy stopped Reduced dose of pegifn and/or RBV Treatment not continued for a sufficient period of time

HCV RNA (log 10 IU/mL) Adjusting Dose Do Not Stop 16 1200 600 0 RBV Dose (mg/d) 12 8 4 Hb (g/dl) 0 0 4 8 12 18 24 30 36 42 48 Weeks

It is difficult for many patients to tolerate even the standard duration of peginterferon alfa and ribavirin therapy. Many studies have suggested that at least 20% patients have adverse events that are severe enough to require either a reduction in the dose of peginterferon alfa and/or ribavirin, a temporary treatment interruption, or a permanent discontinuation of treatment.

Neither peginterferon alfa nor ribavirin dosing should be interrupted unless the adverse event is particularly severe and there is a concern for patient safety.

Relapse (%) Impact of RBV Dose after 12 Weeks 80 Patients received > 97% of RBV during Weeks 1-12 60 40 20 17 17 40 56 Completed all 48 weeks of treatment Any reduction in RBV dose occurred after Week 12 0 > 97 97-81 80-61 60-0 Cumulative Ribavirin Dose (%) n = 218 65 31 11 Reddy KR, et al. Clin Gastroenterol Hepatol. 2007;5:124-129.

Peginterferon 2b + Ribavirin Sustained Virologic Response by Weight <65 kg 65-85 kg >85 kg 57% 48% 41% 47% 49% 46% 62% 55% 49% 3 MIU + ribavirin 1,000 mg-1,200 mg Schering Corporation, data on file Manns et al., Lancet 2001 PEG 0.5 g/kg + Ribavirin 1,000 mg-1,200 mg PEG 1.5 g/kg + Ribavirin 800 mg

Why Patients Fail HCV Therapy Noncompliance with physician recommendations Inherently resistant to IFN Response not recognized Adverse events Therapy stopped Dose of pegifn and/or RBV reduced Treatment not continued for a sufficient period of time

Adherence to therapy Patients achieving the 80/80/80 adherence goal: Taking 80% of the interferon dose And 80% of the ribavirin dose For 80% of the expected duration of therapy.

Why Retreat?

Two Schools of Thought: Retreat Now vs. Wait for Newer Agents Before Retreating RETREAT NOW WAIT TO RETREAT Eradicate virus Concerns about efficacy Stop or reverse fibrosis Side effects of therapy Decrease risk of HCC New antivirals coming soon

Who Can Benefit from Retreatment?

When Considering Retreatment, Results from Small-Scale Studies Using PEG-IFN alfa-2b Aid Patient Selection Factor Initial Treatment Response (Relapser vs. Nonresponder) Study Parameters N=152 (Relapsers=4 6; N/R=95). 48 wks of treatment Genotype N=182 (G1=87%). 48 wks of treatment Retreatment Baseline Viral Load N=141 (52%=HVL). 48 wks of treatment Impact on Retreatment SVR Relapsers more likely to achieve retreatment SVR 1 Genotype 2 and 3 are more likely to achieve retreatment SVR 2 Baseline low viral load more likely to achieve retreatment SVR 3

How Should We Approach Retreatment?

Management Strategies Increase induction dose of pegifn + weight-based RBV Initiate treatment with albumin IFN + weight-based RBV Low-dose pegifn to manage sequelae Watch and wait

Options in PegIFN + RBV Nonresponders Retreat in the event of poor adherence to previous therapy Longer course of treatment for relapsers Extrapolation of 48- vs 72-wk results in slow responders Other IFNs (consensus IFN, albumin IFN) Maintenance therapy Clinical trials of new agents Watching and waiting : an option not to be ignored

HCV RNA (log 10 IU/mL) Partial Responder: Impact of Intensifying Therapy 8 7 6 PegIFN/RBV 5 4 3 2 1 Partial response 2 log decline Limit of detection 0 0 4 8 12 18 24 30 36 42 48 54 60 66 72 78 Weeks

HCV RNA (log 10 IU/mL) Partial Responder: Impact of Intensifying Therapy (cont d) 8 7 6 5 4 3 2 1 0 PegIFN/RBV Intensify PegIFN dose Weeks 2 log decline Limit of detection 0 4 8 12 18 24 30 36 42 48 54 60 66 72 78 SVR

SVR (%) Slow-to-Respond Patients: Extending Therapy 100 48 weeks 72 weeks 80 77 60 46 44 40 33 31 20 16 RBV dose (mg/day) = 0 Berg 800 Sanchez-Tapias 800 Ferenci 1000-1200 Berg T, et al. Gastroenterology. 2006;130:1086-1097. Sanchez-Tapias JM, et al. Gastroenterology. 2006;131:451-460. Ferenci P, et al. AASLD 2006. Abstract 390.

SVR (%) HALT-C: Retreatment of Standard IFN Nonresponders With PegIFN + RBV PegIFN alfa-2a 180 µg/wk + RBV 1000-1200 mg/day Patients with bridging fibrosis or cirrhosis included If viral clearance achieved at 20 wks continue treatment through 48 wks 100 90 80 70 60 50 40 30 20 10 0 HCV RNA Positive, Previous Nonresponders to IFN ± RBV 18 All Patients (N = 604) Shiffman ML, et al. Gastroenterology. 2004;126:1015-1023. 28 NR: IFN (n = 219) P <.0001 12 NR: IFN + RBV (n = 385)

SVR (%) RENEW: Higher-Dose PegIFN alfa-2b Increases SVR Rate 100 90 80 70 60 50 40 30 20 10 0 IFN + RBV Nonresponders* Treated With RBV 800-1400 mg/day and PegIFN -2b 1.5 µg/kg or 3.0 µg/kg for 48 Wks (N = 704) 12 P =.03 1.5 µg/kg/wk (n = 352) 3.0 µg/kg/wk (n = 352) 17 *91% genotype 1. Gross J, et al. 2005 AASLD. Abstract 80. PegIFN alfa-2b Dose

Patients (%) REPEAT: No Benefit Associated With High-Dose Induction 100 80 60 40 20 0 49 31 33 31 28 16 14 7 9 PegIFN alfa-2a 360/180 μg/wk Modified ITT* ETR Relapse SVR P =.006 (OR: 2.0; 95% CI: 1.21-3.31) 78 72 wk (n = 317) 48 wk (n = 156) 72 wk (n = 156) 48 wk (n = 313) 59 67 PegIFN alfa-2a 180 μg/wk Extended treatment did not increase ETR but did decrease relapse *Patients randomized who received at least one dose of study medication Jensen D, et al. AASLD 2007. Abstract LB4.

Testing a Stringent Week 12 Stopping Rule with PEG-IFN alfa-2b: EPIC 3 Retreatment Study Design Patients enrolled on or before April 1, 2004 n = 1354 Efficacy population n = 1336 HCV RNA undetectable** n = 499 12 Weeks* HCV RNA Positive with >2 log drop in HCV RNA n = 293 HCV RNA Positive with <2 log drop in HCV RNA n = 457 n = 143 Completed 48 weeks of therapy and 24-week follow-up n = 650 Entered maintenance protocols or discontinued n = 599 *87 patients did not have 12-week data; 1 missing baseline HCV RNA **LLD <125 IU/mL Continued in the protocol at the discretion of the investigator Poynard T, et al. HepDART 2007, Poster 110.

% Patients Efficacy Results Overall by Prior Treatment 50% 40% Proportion of Patients Achieving SVR PegIntron (1.5 µg/kg/w) + Ribavirin (800-1400 mg/d), 48 weeks 30% 23% 25% 20% 16% 10% 0% Overall Prior Prior n = 1336 IFN + RBV PEG-IFN + RBV n = 1030 n = 299 Poynard T, et al. HepDART 2007, Poster 110. PegIntron SmPC

% Patients Whether Prior Therapy Was with Pegylated or Non-Pegylated IFN, Prior Relapsers More Likely to Achieve Retreatment SVR 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Proportion of Patients Achieving SVR PegIntron (1.5 µg/kg/w) + Ribavirin (800-1400 mg/d), 48 weeks 15% 41% 28% 17% 45% 30% 4% 36% 7% Overall Prior Prior n = 1336 IFN + RBV PEG-IFN + RBV n = 1030 n = 299 Nonresponder Relapser Treatment Failure Schering-Plough. Data on File

% Patients Overall, Relapsers Were More Likely to Achieve Viral Negativity at Treatment Week 12 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Proportion of Patients Achieving EVR as a Function of Prior Virologic Response PegIntron (1.5 µg/kg/w) + Ribavirin (800-1400 mg/d), 48 weeks 66% 25% 43% Prior Prior Prior Relapsers Nonresponders Treatment Failures Schering-Plough Data on File.

% Patients The Week 12 Response Is Highly Predictive of SVR Regardless of Genotype 100% 90% 80% 70% 60% 50% 40% 30% 57% 59% 27% 48% Proportion of Patients Achieving SVR PegIntron (1.5 µg/kg/w) + Ribavirin (800-1400 mg/d), 48 weeks 74% 72% 60% 33% G1 G2 G3 G4 20% 16% 15% 10% 0% Overall Undetectable HCV RNA 5% 0% Detectable HCV RNA But >2 log decrease Poynard T, et al. HepDART 2007, Poster 110. Week 12

The New Week 12 Retreatment Milestone Derived from EPIC 3 Response Analyses HCV RNA Week 12 Detectable Undetectable Consider Stopping Treatment Continue Treatment for 48 Weeks EPIC 3 data establish a Week 12 decision point for continuing retreatment with PEG-IFN + RBV Patients with undetectable HCV RNA at Week 12 have a >50% chance of attaining an SVR For those with detectable HCV RNA at Week 12, the odds of attaining an SVR are low

Summary -Depending on the reasons for initial failure, many patients are likely to achieve SVR with a second course of treatment -In the EPIC 3 study, SVR was attained by 23% of patients overall -Among those who were negative at week 12 57% achieved SVR: 59% of prior non-pegylated failures and 47% of prior pegylated failures -Applying a stringent week 12 stopping rule can be a powerful motivator to encourage patients toward another course of treatment.

Novel Agents in Development

SVR 12 (%) DIRECT: cifn 9 µg vs 15 µg + RBV in PegIFN/RBV Nonresponders 100 90 80 70 60 50 40 30 20 10 0 0 No Treatment (n = 172) P =.002 Modified ITT* 5.3 9 µg cifn + RBV (n = 245) P <.001 9.5 15 µg cifn + RBV (n = 242) *Patients with at least 12 wks of viral negativity after end of treatment; RBV dosed at 1000-1200 mg/day. Bacon B, et al. AASLD 2007. Abstract 168.

DIRECT: Summary Patients with lower fibrosis stages experienced improved responses with cifn Noncirrhotic patients with greater HCV RNA reductions during previous pegifn/rbv therapy had the best response 15 µg cifn group consistently experienced a better response than the 9 µg cifn group cifn/rbv had an acceptable tolerability profile at doses up to 15 µg Bacon B, et al. AASLD 2007. Abstract 168.

SVR (%) Boceprevir + PegIFN/RBV: Phase II Nonresponder Study, GT 1 Response dependent on interferon responsiveness 100 80 Patients With Detectable HCV RNA or < 2 log 10 Decline in HCV RNA at 12 Wks of Previous PegIFN + RBV (N = 357) 60 40 20 7-14 2 0 PegIFN -2b + RBV Boceprevir* + PegIFN -2b + RBV (Various Arms) *100, 200, 400, and 800 mg TID boceprevir. Schiff E, et al. EASL 2008. Abstract 104.

Conclusion: Management of PegIFN + RBV Nonresponders Consider longer duration of retreatment in relapsers Potential benefit of pegifn alfa-2a/b crossover concept still to be proven Optimize weight-based RBV dose in retreated patients Higher doses of pegifn alfa may be superior to standard dose in selected patients

Conclusion: Management of PegIFN + RBV Nonresponders Potential role for cifn in selected patients (eg, partial responders, noncirrhotics, relapsers) Longer treatment durations in nonresponders should be considered, depending on viral kinetics, tolerability, degree of fibrosis Maintenance therapy of uncertain efficacy Watch and wait approach is reasonable in many patients