Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net loss	$ (116,045)	$ (133,816)	$ (121,755)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	26,795	28,216	26,969
Depreciation and amortization expense	2,336	2,371	2,973
Non-cash interest expense associated with the sale of future royalties	(135)	5,148	0
Non-cash royalty revenue	2,350	(10,318)	0
Premium paid on marketable securities	0	(73)	(846)
Amortization (accretion) of premiums (discounts) on marketable securities	(1,138)	(2,856)	1,171
Loss on disposal of property and equipment	16	150	0
Change in fair value of Series 1 nonconvertible preferred stock	(73)	0	(83)
Change in operating assets and liabilities:
Accounts receivable	1,968	11,704	3,258
Prepaid expenses and other current assets	850	182	743
Income tax receivable	(995)	(2,286)	8,537
Operating lease, right-of-use assets	6,096	4,598	4,776
Other long-term assets	709	(107)	(604)
Accounts payable	(414)	(1,151)	(4,634)
Accrued expenses	(5,646)	(2,558)	(1,477)
Operating lease liabilities	4,994	(2,567)	(3,706)
Other long-term liabilities	(432)	209	(104)
Net cash used in operating activities	(78,764)	(103,154)	(84,782)
Cash flows from investing activities
Purchase of marketable securities	(307,282)	(373,391)	(171,446)
Proceeds from maturities and sale of marketable securities	383,465	328,871	228,468
Purchase of property and equipment	(17,948)	(9,058)	(2,125)
Net cash provided by (used in) investing activities	58,235	(53,578)	54,897
Cash flows from financing activities
Payments on royalty sale liability, net of imputed interest	(27,479)	0	0
Proceeds from the exercise of stock options	147	2,208	21,262
Proceeds from the sale of future royalties	0	200,000	0
Payments for debt issuance costs	0	(325)	0
Payments for settlement of share-based awards	(294)	(3,757)	(1,229)
Net cash provided by (used in) financing activities	(27,626)	198,126	20,033
Net increase (decrease) in cash, cash equivalents and restricted cash	(48,155)	41,394	(9,852)
Cash, cash equivalents and restricted cash at beginning of period	89,356	47,962	57,814
Cash, cash equivalents and restricted cash at end of period	41,201	89,356	47,962
Supplemental disclosure of cash flow information
Cash paid for taxes	241	4,899	0
Cash paid for interest	11,710	1,987	0
Cash received from tenant improvement allowances	9,358	1,994	0
Supplemental disclosure of noncash information:
Purchases of fixed assets included in accounts payable and accrued expenses	5,597	424	1,215
Operating lease liabilities arising from obtaining right-of-use assets	$ 23,960	$ 3,817	$ 23,910