Note 9 - Subsequent Event	3 Months Ended
Mar. 31, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	Note 9 — Subsequent Event In January 2021, the Ministry of Health, Labor and Welfare in Japan granted marketing and manufacturing approval for ORLADEYO for prophylactic treatment of hereditary angioedema in adults and pediatric patients 12 years and older. On April 14, 2021, the Company announced that the Japanese National Health Insurance System (“NHI”) approved the addition of oral, once-daily ORLADEYO™ (berotralstat) to the NHI drug price list on April 21, 2021. This triggered a $15,000 milestone payment to the Company from Torii. The Company will record the $15,000 milestone revenue in the second quarter of 2021.Torii launched ORLADEYO in Japan on April 23, 2021. The Company will receive tiered royalties ranging from 20 percent to 40 percent of Japanese net sales (See Note 8, Collaborative Agreements).

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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