Promissory Notes Payable to Related Parties | Promissory Notes Payable to Related Parties Non-current and current debt consisted of the following: Current notes Non-current notes December 31, 2022 December 31, 2021 December 31, 2022 December 31, 2021 Principal amounts $ 20,000 $ — $ 500,000 — Debt discount (230) — (5,460) $ — Total promissory notes payable to related parties $ 19,770 $ — $ 494,540 $ — March 2022 Promissory Note On March 10, 2022, Mr. Duggan, entered into a Note Purchase Agreement (the “March 2022 Note”), pursuant to which he loaned the Company $25,000 in exchange for the issuance by the Company of an unsecured promissory note in the amount of $25,000. The March 2022 Note accrued interest at a rate per annum equal to the prime rate as reported in the Wall Street Journal . The March 2022 Note, including all accrued interest, became due upon the earlier of (i) the consummation of a registered public offering with net proceeds of no less than $25,000 or (ii) 18 months from the date of issuance of the March 2022 Note. Debt issuance costs associated with the March 2022 Note were immaterial and expensed as incurred. The March 2022 Note of $25,000, plus accrued interest of $434 has been repaid to Mr. Duggan on August 10, 2022 in connection with the completion of the rights offering with aggregate gross proceeds of $100,000. The Company incurred interest expense of $1,296 for the year ended December 31, 2022, which included amortized imputed interest of $861 for the year ended December 31, 2022. December 2022 Promissory Notes On December 6, 2022, the Company entered into a Note Purchase Agreement (the "Note Purchase Agreement"), with Mr. Duggan and Dr. Zanganeh, pursuant to which the Company agreed to sell to each of Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520,000. Pursuant to the Note Purchase Agreement, the Company issued to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the amount of $400,000 (the "Duggan February Note") and $20,000 (the "Zanganeh Note"), respectively, which would mature and become due on February 15, 2023 and an unsecured promissory note to Mr. Duggan in the amount of $100,000 (the “Duggan September Note” and together with the Duggan February Note and the Zanganeh Note, the “December 2022 Notes”), which will mature and become due on September 15, 2023. The maturity dates of the December 2022 Notes could be extended one or more times at the Company’s election, but in no event to a date later than September 6, 2024. In addition, if the Company shall consummate a public offering, then upon the later to occur of (i) five On January 19, 2023, the Company provided notice to extend the term of the Duggan February Note and Duggan September Note to a maturity date of September 6, 2024. Furthermore, on January 19, 2023, the Company and Mr. Duggan rectified the Duggan February Note and Duggan September Note in order to correctly reflect the parties’ intent that the Company may only prepay (i) the Duggan February Note following the completion of a public rights offering to be conducted by Summit in the approximate amount of $500,000 (the “Rights Offering”), or a similar capital raise, in an amount equal to the lesser of (x) the net proceeds of the Rights Offering or such capital raise or (y) the full amount outstanding of the Duggan February Note, and (ii) Duggan September Note following the completion of a capital raising transaction subsequent to the Rights Offering in an amount equal to the lesser of (i) the net proceeds of such capital raise or (ii) the full amount outstanding of the Duggan September Note. Following the issuance of the two new Promissory Notes (the “Duggan Promissory Notes”), the Duggan February Note and Duggan September Note were marked as “cancelled” on their face and replaced in their entirety by the Duggan Promissory Notes (together with the Zanganeh Note, the "Notes"). The Notes accrue interest at an initial rate of 7.5%. All interest on the Notes shall be paid on the date of signing for the period through February 15, 2023. Such prepaid interest shall be paid in a number of shares of the Company’s common stock, par value $0.01 (“Common Stock”) equal to the dollar amount of such prepaid interest, divided by $0.7913 (the consolidated closing bid price immediately preceding the time the Company entered into the Note Purchase Agreement, plus $0.01), which was 9,720,291 shares. For all applicable periods following the February 15, 2023, interest shall accrue on the outstanding principal balance of the Notes at the US prime interest rate, as reported in the Wall Street Journal, plus 50 basis points, as adjusted monthly, for three months immediately following February 15, 2023, and thereafter at the US prime rate plus 300 basis points, as adjusted monthly. Debt issuance costs associated with the Notes were $44 and we capitalized as part of the carrying value of the promissory notes payable to related parties. The Company incurred interest expense of $3,105 for the year ended December 31, 2022, which included amortized imputed interest of $395. Imputed interest is calculated as the difference between the expected interest payable and the deemed market rate of interest and is recorded as a debt discount at inception of the note payable with a credit to additional paid-in capital for notes payable to related parties. The debt discount is amortized to interest expense using an effective interest rate method. The effective interest rate of the Duggan February Note and Zanganeh Note was 8.7% and the effective interest rate of the Duggan September Note was 8.8%. The Company incurred interest expense of $244 for the year ended December 31, 2021, which included amortized imputed interest $159 for the year ended December 31, 2021, respectively, related to the March 24, 2021 Note Purchase Agreement with Mr. Duggan, for $55,000 which was subsequently rescinded and replaced by a second note on April 20, 2021, of the same amount, and paid in full in May 2021, as described further in Note 22. As of December 31, 2022, and reflecting the Company's election to extend the term of the Duggan February Note and the Duggan September Note, the estimated future principal payments due were as follows: Year Ending December 31, 2023 $ 20,000 2024 500,000 $ 520,000 On February 15, 2023, the $20,000 Zanganeh Note matured and the Company repaid the outstanding principal balance. In connection with the closing of the rights offering, the $400,000 Duggan Promissory Note matured and became due, and the Company repaid all principal and accrued interest thereunder using a portion of the proceeds from this rights offering. March 24, 2021 Note Purchase Agreement On March 24, 2021, Mr. Duggan, the Company's Executive Chairman and Chief Executive Officer and primary stockholder, entered into a Note Purchase Agreement (the “Initial 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 “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 United States Treasury rate, as adjusted monthly. The rate was 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. April 20, 2021 Note Purchase Agreement On April 20, 2021, subsequent to the repayment of the Initial Note, Mr. 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 United States 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 ("2021 Rights Offering") On May 12, 2021, the Company closed its 2021 Rights Offering, which was fully subscribed. Aggregate gross proceeds from the 2021 Rights Offering were $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. Duggan and 389,977 shares were purchased by Dr. Zanganeh, at price of $5.24 per share. In connection with the closing of the 2021 Rights Offering, the Second Note, issued by the Company to Mr. Duggan, matured and became due and was repaid using a portion of the proceeds from the 2021 Rights Offering. March 26, 2021 Sublease Agreement with Maky Zanganeh and Associates, Inc. On March 26, 2021, the Company entered into a sublease with Maky Zanganeh and Associates, Inc. ("MZA") consisting of 4,500 square feet of office space at 2882 Sand Hill Road, Menlo Park, California (the “Sublease”). Dr. Zanganeh, the Company's Co-Chief Executive Officer and President, is the sole owner of MZA. The sublease ran until September 2022. The rent payable under the terms of the sublease was 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 years ended December 31, 2022 and 2021, payments of $544 and $556, were made pursuant to the sublease. July 25, 2022 First Amendment to Sublease Agreement with Maky Zanganeh and Associates, Inc. On July 25, 2022 the Company entered into a first amendment, dated July 19, 2022, to its existing sublease agreement with MZA, described above. The existing sublease term, which was set to expire on September 30, 2022, was extended for a period of thirty-nine months from October 1, 2022 through December 31, 2025. The rent payable under the terms of the sublease is equivalent to the proportionate share of the net 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. July 29, 2022 Second Amendment to Sublease Agreement with Maky Zanganeh and Associates, Inc. On July 29, 2022, the Company entered into a second amendment, dated August 1, 2022, to its existing sublease agreement with MZA, described above. The second amendment was effective as of August 1, 2022 and expires on December 31, 2025. The second amendment includes an additional 1,277 square feet (the "Expansion Premises") of office space at 2882 Sand Hill Road, Menlo Park, California. The rent payable under the terms of the sublease is equivalent to the proportionate share of the net 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, 2022 payments of $54, were made pursuant to the secondment amendment to the sublease. March 10, 2022 Note Purchase Agreement On March 10, 2022, the Company entered into a Note Purchase Agreement (the "March 2022 Note"), with Mr. Duggan, pursuant to which Mr. Duggan loaned the Company $25,000 in exchange for the issuance by the Company of an unsecured promissory note in the amount of $25,000. The March 2022 Note accrued interest at a rate per annum equal to the prime rate as reported in the Wall Street Journal , which was 3.25% as of the effective date and 4.75% as of June 30, 2022. The March 2022 Note, including accrued interest, became due upon the earlier of (i) the consummation of a registered public offering with net proceeds of no less than $25,000 or (ii) 18 months from the date of issuance of the March 2022 Note, and was repaid on August 10, 2022. 2022 Rights Offering ("2022 Rights Offering") In August 2022, the Company announced the closing and final results of its previously announced rights offering. The 2022 Rights Offering commenced on July 18, 2022, and the associated subscription rights expired on August 8, 2022. Aggregate gross proceeds received from the rights offering were $100,000 from the sale of 103,092,783 shares of common stock. Mr. Duggan and Dr. Zanganeh fully subscribed to their respective basic subscription rights and oversubscribed, at a price of $0.97 per share. Issuance costs were $111. In connection with the closing of the 2022 Rights Offering, the March 2022 Note matured and became due, and the Company repaid all principal and accrued interest thereunder using a portion of the proceeds from the 2022 Rights Offering on August 10, 2022. December 6, 2022 Note Purchase Agreement On December 6, 2022, the Company entered into a Note Purchase Agreement (the "Note Purchase Agreement"), with Mr. Duggan and Dr. Zanganeh, pursuant to which the Company agreed to sell to each of Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520,000. Pursuant to the Note Purchase Agreement, the Company issued to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the amount of $400,000 (the "Duggan February Note") and $20,000 (the "Zanganeh Note"), respectively, which would mature and become due on February 15, 2023 and an unsecured promissory note to Mr. Duggan in the amount of $100,000 (the “Duggan September Note” and together with the Duggan February Note and the Zanganeh Note, the “December 2022 Notes”), which will mature and become due on September 15, 2023. The maturity dates of the December 2022 Notes could be extended one or more times at the Company’s election, but in no event to a date later than September 6, 2024. In addition, if the Company shall consummate a public offering, then upon the later to occur of (i) five On January 19, 2023, the Company provided notice to extend the term of the Duggan February Note and Duggan September Note to a maturity date of September 6, 2024. Furthermore, on January 19, 2023, the Company and Mr. Duggan rectified the Duggan February Note and Duggan September Note in order to correctly reflect the parties’ intent that the Company may only prepay (i) the Duggan February Note following the completion of a public rights offering to be conducted by Summit in the approximate amount of $500,000 (the “Rights Offering”), or a similar capital raise, in an amount equal to the lesser of (x) the net proceeds of the Rights Offering or such capital raise or (y) the full amount outstanding of the Duggan February Note, and (ii) Duggan September Note following the completion of a capital raising transaction subsequent to the Rights Offering in an amount equal to the lesser of (i) the net proceeds of such capital raise or (ii) the full amount outstanding of the Duggan September Note. Following the issuance of the two new Promissory Notes (the “Duggan Promissory Notes”), the Duggan February Note and Duggan September Note were marked as “cancelled” on their face and replaced in their entirety by the Duggan Promissory Notes (together with the Zanganeh Note, the "Notes"). The Notes accrue interest at an initial rate of 7.5%. All interest on the Notes shall be paid on the date of signing for the period through February 15, 2023. Such prepaid interest shall be paid in a number of shares of the Company’s common stock, par value $0.01 (“Common Stock”) equal to the dollar amount of such prepaid interest, divided by $0.7913 (the consolidated closing bid price immediately preceding the time the Company entered into the Note Purchase Agreement, plus $0.01), which was 9,720,291 shares. For all applicable periods following the February 15, 2023, interest shall accrue on the outstanding principal balance of the Notes at the United States prime interest rate, as reported in the Wall Street Journal, plus 50 basis points, as adjusted monthly, for three months immediately following February 15, 2023, and thereafter at the United States prime rate plus 300 basis points, as adjusted monthly. |