Press Releases.

On Track to Deliver Follow-up Results from On-going RG-101 Studies

Conference Call and Webcast to Follow

Timelines of On-going Studies are not Expected to be Impacted

- Results Demonstrate First Successful Shortened 4-week Treatment Regimen to Date -

- Phase II Study Evaluating the Combination of RG-101 and GSK's Long-Acting Parenteral (LAP) Formulation of GSK2878175 as a potential single-visit cure to begin Q4 2016

- Continued High Virologic Response Rates across All Treatment Arms Out through 24 weeks of Follow Up -

-Oral presentation during general session on interim RG-101 Phase II results & three posters to be presented-

- RG-101 Containing Regimen Has Potential to Reduce Harvoni®, Olysio®, or Daklinza™ Rx to 4 Week Duration -

- Additional studies on track for enrollment in H12016 with multiple data read-outs expected throughout 2016 -

-Regulus Earns $10.0 Million Milestone Payment from AstraZeneca and Achieves Key Goal for 2015-