hepatitis C virus (HCV) has traditionally been treated in subspecialty health centers given the complexity of older pegylated interferon containing regimens, formerly the standard of care. This model has persisted into the modern era of direct anti-viral agents (DAAs) despite their relative simplicity, creating a bottleneck of human resources necessary to fight the largest infectious epidemic in North America. In addition, stigma and fear over cost has lead payers to restrict treatment in People Who Inject Drugs (PWIDs), even though a majority of new infections occur in this population.

This study evaluates the effectiveness of treatment of HCV with elbasvir-grasoprevir in PWIDs in a real world, community health clinic setting.

There are two prospective cohorts of PWIDs of 25 patients each, both in primary care-based community health clinics in Portland, Oregon. Cohort one is actively engaged with ambulatory medication assisted therapy with buprenorphine or extended released injectable naltrexone. Cohort two maintains active injection drug use with needle exchange and risk reduction education.

These groups are compared to a 50 patient retrospective cohort of people with substance use disorders at tertiary care hepatology-based treatment program.

All patients have genotype 1 or 4 HCV and are treated with elbasvir-grasoprevir for 12 weeks.

The investigators hypothesize there is no difference in sustained viremic response at 12 or 48 weeks post-completion of treatment (SVR 12, 48) when treating patients in a community health clinic setting as compared to the standard-of-care subspecialty setting.

Hepatitis C has traditionally been treated in subspecialty health centers given the complexity of older pegylated interferon containing regimens, formerly the standard of care. This model has persisted into the modern era of direct anti-viral agents (DAAs) despite their relative simplicity, creating a bottleneck of human resources necessary to fight the largest infectious epidemic in North America. In addition, stigma and fear over cost has lead payers to restrict treatment in People Who Inject Drugs (PWIDs), even though a majority of new infections occur in this population.

This study evaluates the effectiveness of treatment of hepatitis C virus (HCV) with elbasvir-grasoprevir in people who inject drugs (PWIDs) in a real world, community health clinic setting.

There are two prospective cohorts of PWIDs of 25 patients each, both in primary care-based community health clinics in Portland, Oregon. Cohort one is actively engaged with ambulatory medication assisted therapy with buprenorphine or extended released injectable naltrexone. Cohort two maintains active injection drug use with needle exchange and risk reduction education.

These groups are compared to a 50 patient retrospective cohort of people with substance use disorders at tertiary care hepatology-based Academic Health Center.

All patients have genotype 1 or 4 HCV and are treated with elbasvir-grasoprevir for 12 weeks. The investigators exclude patients who: are under the age of 18; have a history of liver transplant; have failed past treatment of HCV; have an Aspartate aminotransferase Platelet Ratio Index (APRI) > 0.7 or APRI >0.7 but fibrosure/fibroscan of F2 or less; patients with genotype 1a and Nonstructural 5a (NS5a) resistance associated variants (RAVs); have clinical or radiologic evidence of cirrhosis; have aminotransferase levels >10x upper limit of normal; have a hemoglobin of less than 11g/dL, and are co-infected with hepatitis B or HIV.

The investigators hypothesize there is no difference in sustained viremic response at 12 or 48 weeks post-completion treatment (SVR 12, 48) when treating patients with a DAA in a community health clinic setting as compared to the standard-of-care subspecialty setting.

Inclusion Criteria:

• Genotype 1b and genotype 1a without baseline NS5A resistance or Genotype 4
• APRI Score <0.7; if >0.7 a Fibrosure/Fibrotest or Fibroscan score of F2 or less
• No clinical or laboratory evidence of cirrhosis
• Readiness for treatment based on ability to make >2/3 sequential office visits
• Patients must be assessed to have decision-making capacity, be capable of consenting, and not be displaying evidence of overt intoxication.

Exclusion Criteria:

• Clinical or Laboratory Evidence of Cirrhosis
• Elevated prothrombin time unrelated to anticoagulation, hemoglobin level less than 12.3 g/L in females and <14 g/L in males, platelet count <150 × 109 cells/L), white blood cells (WBC) <4.0 x103/mm3 , aminotransferase levels more than 10 times the upper limit of normal, or albumin level <3.5 g/L.
• Previous treatment for hepatitis C infection
• Hepatocellular carcinoma
• HIV or hepatitis B virus co-infection
• Subjects taking medications that are contra-indicated to administer with Zepatier including phenytoin, carbamazepine, rifampin, St. John's Wort, and cyclosporine AND unable to change these medications to one without interactions.

All electronic data will be maintained encrypted in the Red Cap repository. Only the primary investigator and co-investigator will have access to the master spreadsheet linking study and personal identifiers. Andrew Seaman, co-investigator and primary study contact, will be listed as the repository guardian. He will be responsible for ensuring data are released according to OHSU policy and the institutional review board (IRB) approved repository protocol, executing a repository sharing agreement in case data are released for future research, ensuring the security and confidentiality of all stored data, ensuring the security and confidentiality of data, and tracking releases of data. The repository guardian will be responsible for verifying that future releases are done in concordance with pre-proposed limits and the original consent. Data transport at the time of any future IRB approved data sharing will be approved by an updated research services agreement and separate IRB approval.

All baseline characteristics were collected on both consented, prospective study groups (MOUD and Needle Exchange Program groups). The retrospective cohort only collected Age, Sex, Race/Ethnicity, Genotype, and APRI score and excluded level of education, duration of primary care establishment, and drug of choice.

Between study enrollment and SVR12 = 24 weeks

Reporting mirrors clinicaltrials.gov definitions. All-Cause Mortality and Other [Not Including Serious] Adverse Events were not monitored/assessed for the OHSU Hepatology Clinic, Academic Center Retrospective Cohort. All serious and other adverse effects were monitored for the two prospective arms, as reported below.

Study groups comparisons of sites of enrollment/treatment (MAT clinic vs needle exchange) rather than disease state (many MAT participants used needle exchange; many needle exchange on MAT); funding limitations prevented SVR48 collection.