Stock-based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) |
12 Months Ended | |
|---|---|---|
Apr. 30, 2022 |
Apr. 30, 2021 |
|
| Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Stock-based compensation | $ 68,396 | $ 24,675 |
| Research and Development | ||
| Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Stock-based compensation | 4,232 | 15,229 |
| Selling, General and Administrative | ||
| Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Stock-based compensation | $ 64,163 | $ 9,446 |