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<link:definition>1019 - Disclosure - Fair Value Measurements (Tables)</link:definition>
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<link:definition>1020 - Disclosure - Net Loss Per Share (Tables)</link:definition>
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<link:definition>1021 - Disclosure - Leases (Tables)</link:definition>
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<link:definition>1023 - Disclosure - The Company and Summary of Significant Accounting Policies - Additional Information (Detail)</link:definition>
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<link:definition>1029 - Disclosure - License Agreements - Additional Information (Detail)</link:definition>
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<link:definition>1030 - Disclosure - Net Loss Per Share - Additional Information (Detail)</link:definition>
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<link:definition>1039 - Disclosure - Stockholders' Equity - Additional Information (Detail)</link:definition>
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