Note 2 - Basis of Presentation, Principles of Consolidation, Significant Accounting Policies and Liquidity - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Vendor prepayments and deposits	$ 557	$ 486
Prepaid sponsored research	329	474
Prepaid insurance	243	589
Related party receivables	22	22
Non-trade receivables	5	23
Total prepaid expenses and other current assets	$ 1,156	$ 1,594

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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+ Details