Financial Statement Details - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Prepaid preclinical and clinical trial services - with related party (Note 9)	$ 2,638	$ 1,021
Prepaid services	553	440
Prepaid rent	414	392
Prepaid supplies - with related party (Note 9)	328	467
Prepaid insurance	189	372
Prepaid equipment maintenance	176	251
Prepaid license fees	160	78
Interest receivable - marketable debt securities	113	222
Due from related parties	26	47
Insurance premium financing asset	0	757
Insurance claim receivables	0	34
Other	67	24
Total prepaid expenses and other current assets	$ 4,664	$ 4,105

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Insurance premium financing asset.

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Prepaid equipment maintenance.

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Prepaid license fees.

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Prepaid preclinical and clinical trial services with related party.

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Prepaid services.

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Prepaid supplies with related party.

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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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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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