Piper Jaffray analyst David Amsellem says his survey of 25 rheumatologists who treat patients with chronic refractory gout and who are at least familiar with Horizon Pharma's Krystexxa suggest usage of the product is likely to broaden. The analyst points out that 76% of the respondents believe Krystexxa is a very effective option for the treatment of chronic refractory gout. He continues to believe Horizon is well positioned to deliver long-term annual earnings growth at least in the mid-teens. Amsellem sees an attractive valuation for Horizon shares and reiterates an Overweight rating on the name with a $33 price target.