 Allena Pharmaceuticals, Inc. ALNA, a late-stage, biopharmaceutical company dedicated to developing and commercializing first-in-class, oral enzyme therapeutics to treat patients with rare and severe metabolic and kidney disorders, today announced that it has reached agreement in principle with the U.S. Food and Drug Administration FDA on a streamlined design for URIROX-2, the second pivotal clinical trial for reloxaliase, a potential first-in-class, non-absorbed, orally administered enzyme for the treatment of severe hyperoxaluria. URIROX-2 is designed to incorporate adaptive design elements that could allow for changes to sample size and duration of treatment based on accrued kidney stone KS disease progression rates and the conditional probability of achieving ultimate statistical success for KS disease progression in the long-term follow-up phase of the trial. 