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Other Current Assets - Schedule of Other Current Assets (Details) - USD ($) $ in Thousands | Apr. 30, 2020 | Apr. 30, 2019
--- | --- | ---
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] |  |
Deposits | $ 60 | $ 63
Other receivables | 2 | 44
Prepaid insurance | 124 | 93
Prepaid offering costs | 275 | 144
Prepaid expenses- other | 127 | 193
Other current assets | $ 588 | $ 537

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