EASL 2018 PS-160
Effects of SB9200 (Inarigivir) therapy on immune responses in
patients with chronic hepatitis B
R. Walsh1, R. Hammond1, K. Jackson1, R. Edwards1, C. Macfarlane2,
R. Iyer2, M.-F. Yuen3, H. Chan4, N. Afdhal2, S. Locarnini1. 1Victorian
Infectious Diseases Reference Laboratory, Australia; 2Spring Bank
Pharmaceuticals, United States; 3University of Hong Kong, Hong Kong;
4The Chinese University of Hong Kong, Hong Kong
Email: [email protected]
Background and Aims: Inarigivir (SB9200) is a small molecule
dinucleotide orally active HBV antiviral with both direct acting and
immune modulatory activity, stimulating the host innate antiviral
response. It binds to the cytosolic pattern recognition receptor
retinoic-acid-inducible gene (RIG-I) to enhance RIG-I binding to the
5’-epsilon region of the HBV pregenomic RNA. The ACHIEVE trial is a
double-blind placebo (PL) controlled study of ascending doses of
Inarigivir PO daily monotherapy or PL for 12 weeks, followed by a
switch to 300 mg Tenofovir daily for a further 12 weeks. We report
here the comparative effects of low dose Inarigivir monotherapy on
the anti-HBs antibody (Ab) response (HBsAg epitope profile, and
complexed Ab) on thirty-eight naive non-cirrhotic HBV patients
randomised 4:1 to twelve weeks of 25 mg or 50 mg Inarigivir or
placebo.
Method and Results: Inarigivir therapy resulted in significant
decline in HBV DNA, HBV RNA and HBcrAg levels in the majority of
treated patients with modest decline in HBsAg. Inarigivir therapy
cohorts (25 mg and 50 mg doses)were further analysed for effects on
immune responses, applying bioassays for developing Ab response
markers predictive of HBsAg clearance including development of
HBsAg clearance profile (CP) and complexed HBsAg/anti-HBs. A
decline in HBV DNA together with the development of a HBsAg CP
during the 12 weeks of Inarigivir therapy was observed in 1/16 (6%)
subjects who received 25 mg of drug, and this response increased to
4/13 (31%) of subjects receiving 50mg of drug. This relationship was
not observed in any PL subjects (n = 8) during the 12weeks treatment
period. The detection of anti-HBs Ab complexed with HBsAg,
indicative of an underlying or emerging immune response, was
enhanced from 2/16 (12%) in the 25 mg treatment cohort, to 6/13
(46%) in the 50mg Inarigivir therapy cohort during the 12 weeks of
treatment. Furthermore, the development of complexed anti-HBs
was enhanced in 6/13 (46%) of patients in the 50mg treatment cohort
compared to the PL arm with only 1/4 (25%) subjects developing
complexed anti-HBs.
Conclusion: Serum biomarkers indicative of Ab responsewere found
to display a strong trend during 12 weeks of Inarigivir therapy
compared to PL. Predictive markers of anti-HBs response were
enhanced in the 50mg versus 25mg Inarigivir therapy cohorts,
revealing a dose response relationship of nascent immune recovery
due to lowdose Inarigivir therapy, suggesting higher doses should be
further studied. 作者: StephenW 时间: 2018-4-3 08:24
Arrowhead and Spring Bank Announce Clinical Collaboration for ARC-520 and SB 9200 in Chronic Hepatitis B
Oct 6, 2016 at 7:30 AM EDT
PASADENA, Calif. & HOPKINTON, Mass. --(BUSINESS WIRE)-- Arrowhead Pharmaceuticals Inc. ( NASDAQ : ARWR) and Spring Bank Pharmaceuticals, Inc. ( NASDAQ : SBPH), a clinical-stage biopharmaceutical company developing novel therapeutics for the treatment of viral infections, cancer, and inflammatory
Arrowhead and Spring Bank Announce Clinical Collaboration for ARC-520 and SB 9200 in Chronic Hepatitis B
PASADENA, Calif. & HOPKINTON, Mass.--(BUSINESS WIRE)-- Arrowhead Pharmaceuticals Inc. (NASDAQ: ARWR) and Spring Bank Pharmaceuticals, Inc. (NASDAQ: SBPH), a clinical-stage biopharmaceutical company developing novel therapeutics for the treatment of viral infections, cancer, and inflammatory diseases, today announced an agreement to perform collaborative studies on Arrowhead's ARC-520 and Spring Bank's SB 9200, for the treatment of chronic Hepatitis B (HBV). The companies plan to first conduct preclinical models with both agents together and then study the agents clinically in a cohort to be added to Arrowhead's ongoing MONARCH Phase 2b study, in which patients will receive a dosing regimen that includes ARC-520, SB 9200, and an oral direct-acting antiviral.
"The MONARCH Phase 2b combination study was specifically designed to be iterative in nature, allowing us to seamlessly add cohorts when additional novel agents are available to study in combination with ARC-520," said Bruce Given, M.D., chief operating officer and head of R&D at Arrowhead. "We see ARC-520, which is designed to silence the production of all HBV gene products, as a potential backbone therapy for combinations. Spring Bank's SB 9200 is a promising immunomodulatory agent with an interesting mechanism that we think has significant therapeutic potential in combination with ARC-520 and a NUC."
"Our collaboration with our colleagues at Arrowhead Pharmaceuticals will be the first study of two completely novel agents in HBV, both focused on delivering a functional cure," said Nezam Afdhal, M.D., chief medical officer at Spring Bank Pharmaceuticals. "We believe combining SB 9200 with Arrowhead's ARC-520, along with an approved nucleotide(side) polymerase inhibitor, has the potential to lead to a functional cure. Together, we hope to demonstrate in the MONARCH trial that triple therapy can increase HBV functional cure rates with a more favorable tolerability profile and perhaps a shorter duration of treatment relative to current standard of care with interferon-based regimens."
About SB 9200
SB 9200 is Spring Bank's novel small molecule, orally-available selective immunomodulator compound being developed as both monotherapy and combination therapy as a backbone for the treatment of chronic HBV and other viral diseases. SB 9200 is currently being studied in the ACHIEVE Phase II global trial. Part A of the ACHIEVE study is a placebo-controlled, sequential cohort, double blind trial to evaluate increasing doses of SB 9200 as monotherapy for 12 weeks followed by tenofovir disoproxil fumarate 300mg (Viread Gilead Sciences Inc.) for a further 12 weeks. Part B of the ACHIEVE study will evaluate SB 9200 in combination with tenofovir and as monotherapy versus tenofovir monotherapy after the optimal doses of SB 9200 are determined in Part A.
About ARC-520
Arrowhead's ARC-520 is being investigated for its potential to produce functional cures in patients with chronic hepatitis B virus (HBV) infection. ARC-520 intervenes upstream of the reverse transcription process where current standard-of-care nucleotide and nucleoside analogs act, and is designed to silence the production of all HBV gene products. The small interfering RNAs (siRNAs) in ARC-520 engage the body's normal cellular RNAi machinery and direct specific cleavage of HBV RNA transcripts, thereby reducing the levels of HBV proteins and the RNA template used to produce viral DNA. Arrowhead is investigating ARC-520 specifically to determine if significantly reducing circulating and non-circulating viral proteins and RNA will allow for re-constitution of an effective host immune response and ultimately HBsAg seroclearance resulting in functional cure. As many as 350-400 million people worldwide are chronically infected with the hepatitis B virus, which can lead to cirrhosis of the liver and is responsible for 80% of primary liver cancers globally. Arrowhead is currently conducting Phase 2b multiple dose and combination studies in chronic HBV patients. In clinical studies to date, the most common reported adverse events in all subjects completing treatment were upper respiratory infection and headache.作者: 齐欢畅 时间: 2018-4-3 22:08