Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions On December 6, 2019, the Company entered into a deed of termination of the relationship agreement with Mr. Robert W. Duggan and Cairn Financial Advisers LLP, a limited liability partnership incorporated in England and Wales with the Registrar of Companies of England and Wales, as the Company's nominated adviser. The relationship agreement regulated the Company’s relationship with Mr. Robert W. Duggan and limited Mr. Robert W. Duggan’s influence over the Company’s corporate actions and activities and the outcome of general matters pertaining to the Company. The deed of termination became effective on February 24, 2020, upon the cancellation of the admission of the ordinary shares on the Alternative Investment Market, a sub-market of the London Stock Exchanges. December 24, 2019 Private Placement On December 24, 2019, the Company completed a private placement of its common stock and received aggregate gross proceeds of $50,000 from the issuance and sale of 35,075,690 shares of common stock at a price of $1.43 per share, of which 33,231,410 shares of common stock were subscribed by Mr. Robert W. Duggan. Also, as part of the private placement, participating investors were granted warrants with the right to subscribe for 5,261,350 shares of common stock at an exercise price of $1.58, of which 4,984,711 were granted to Mr. Robert W. Duggan at an exercise price of $1.43 per share for a subscription share plus a subscription warrant, pursuant to a securities purchase agreement he entered into with the Company. In conjunction with the December 24, 2019 private placement, 90,495 shares of common stock were subscribed by Mr. Glyn Edwards, the Company's former Chief Executive Officer. Also as part of this private placement, Mr. Glyn Edwards was granted warrants with the right to subscribe for 13,574 shares of common stock at an exercise price of $1.43 per share for a subscription share plus a subscription warrant, pursuant to a securities purchase agreement he entered into with the Company. November 6, 2020 Private Placement On November 6, 2020 the Company completed a private placement of its common stock and received gross proceeds of $50,000 from the issuance and sale of 14,970,060 shares of common stock at a price of $3.34 per share, of which 14,071,856 shares of common stock were subscribed by Mr. Robert W. Duggan. In conjunction with the November 6, 2020 private placement, 149,701 shares of common stock were subscribed by the Mahkam Zanganeh Revocable Trust. Dr. Maky Zanganeh was appointed to the Board of Directors on November 11, 2020 and became the Company's Chief Operations Officer on November 22, 2020. As trustee of the Mahkam Zanganeh Revocable Trust, Dr. Maky Zanganeh is deemed to beneficially own the securities of the Company held by the Mahkam Zanganeh Revocable Trust. Consultancy Agreements In 2020, the Company had in place a consultancy agreement with Dr. Maky Zanganeh and Associates, Inc. (“MZA”) to provide support for clinical operation activities related to the global Phase III clinical program. Dr. Maky Zanganeh is the sole owner of MZA, and Dr. Elaine Stracker, who served for a period during fiscal year 2020 as a director of the Company and as the Company’s Interim Chief Operations Officer, was at the time the General Counsel and Senior Vice President for Corporate Development at MZA. The fees for such services under the consultancy agreement with MZA were $75 per month. In addition to such monthly fee, MZA was granted warrants over 3,358,732 shares of common stock with an exercise price of $1.44 per share, vesting on a quarterly basis over three years from the date of grant, subject to MZA’s provision of consultancy services to the Company during such period. During the period of MZA's engagement, $470 of consultancy fees were incurred by the Company and a warrant expense of $512 was recognized. The consultancy agreement with MZA was terminated by mutual agreement on June 30, 2020. The warrants granted to MZA were subsequently assigned to Dr. Maky Zanganeh and Dr. Elaine Stracker. Dr. Maky Zanganeh and Dr. Elaine Stracker have vested warrants to purchase 489,815 and 69,972 shares of common stock, respectively, which can be exercised through June 30, 2025. March 24, 2021 Note Purchase Agreement On March 24, 2021, Mr. Robert W. Duggan, entered into a Note Purchase Agreement (the “Initial Purchase Agreement”) pursuant to which he has loaned the Company $55,000 in exchange for the issuance by the Company of an unsecured promissory note (the “Initial Note”) in the amount of $55,000. The Initial Note was to accrue interest at a rate per annum equal to 150% of the applicable 10 Year U.S. Treasury rate, as adjusted monthly. The rate is initially estimated to be approximately 2.4%. The terms of the Initial Note were that it would mature and become due upon the earlier of (i) the consummation of a registered public offering with net proceeds of no less than $55,000, or (ii) 13 months from the date of issuance of the Initial Note. On April 20, 2021, the Company determined, with Mr. Duggan’s agreement, to rescind both the Initial Purchase Agreement and the Initial Note issued thereunder, and repaid the principal amount of the Initial Note in full, without interest or penalty, as such for the year ended December 31, 2021, the Company recognized imputed interest of $103 within additional paid in capital. For the year ended December 31, 2021, debt issuance costs recognized related to the Initial Note were immaterial. March 26, 2021 Sublease Agreement with Dr. Maky Zanganeh and Associates, Inc. On March 26, 2021, the Company entered into a sublease with Dr. Maky Zanganeh and Associates, Inc. ("MZA") consisting of 4,500 square feet of office space at 2882 Sand Hill Road, Menlo Park, CA (the “Sublease”). Dr. Maky Zanganeh is the sole owner of MZA. The sublease runs until September 2022. The rent payable under the terms of the sublease is equivalent to the proportionate share of the rent payable by MZA to the third-party landlord, based on the square footage of office space sublet by the Company, and no mark-up has been applied. During the year ended December 31, 2021, payments of $556, were made pursuant to the sublease. April 20, 2021 Note Purchase Agreement On April 20, 2021, subsequent to the repayment of the Initial Note, Mr. Robert W. Duggan entered into a second Note Purchase Agreement (the “Second Purchase Agreement”) pursuant to which he loaned the Company $55,000 in exchange for the issuance by the Company of an unsecured promissory note (the “Second Note”) in the amount of $55,000. The Second Note accrued interest at a rate per annum equal to 150% of the applicable 10 Year US Treasury rate, as adjusted monthly (initially estimated to be approximately 2.4%). The Company was permitted to prepay any portion of the second note at its option without penalty. May 12, 2021 Rights Offering On May 12, 2021, the Company closed its rights offering, which was fully subscribed. Aggregate gross proceeds from the rights offering of $75,000 from the sale of 14,312,976 shares of the Company's common stock, of which 11,365,921 shares were purchased by Mr. Robert W. Duggan and 389,977 shares were purchased by Dr. Maky Zanganeh, at price of $5.24 per share. In connection with the closing of the rights offering, the Second Note, issued by the Company in favor of Mr. Robert W. Duggan, matured and became due and was repaid using a portion of the proceeds from the rights offering.