Note 7. California Institute of Regenerative Medicine Awards

The Company has been awarded funding from California Institute of Regenerative Medicine (“CIRM”) to develop internal programs. Under the terms of the funding, both CIRM and the Company have co-funded specified programs, under which funding is provided in developmental milestones determined as a part of the award. The Company is obligated to share potential future revenues for the related programs with CIRM. The percentage of revenues due to CIRM in the future is dependent on the amount of the award received and whether revenue is from product sales or through license fees. The maximum revenue sharing amount the Company may be required to pay to CIRM is equal to nine times the total amount awarded and paid to the Company. The Company has the option to decline any and all amounts awarded by CIRM. As an alternative to revenue sharing, the Company has the option to convert the award

to a loan, which such option the Company must exercise on or before ten business days after the FDA notifies the Company that it has accepted the Company’s application for marketing authorization. In the event the Company exercises its right to convert any award to a loan, it would be obligated to repay the loan within ten business days of making such election. Repayment amounts due to CIRM vary dependent on when the award is converted to a loan, ranging from 60% of the award granted to the full amount received plus interest at the rate of the three-month LIBOR rate plus 10% per annum. Since the Company may be required to repay some or all of the amounts awarded by CIRM, the Company accounts for these awards as a liability rather than revenue if the Company’s intention is to convert the awards into a loan. Given the uncertainty in amounts due upon repayment, the Company has recorded amounts received without any discount or interest recorded, upon determination of amounts that would become due, the Company will adjust accordingly.

In December 2017, the Company was granted an award in the amount of $19.8 million from CIRM to support the Company’s P-BCMA-101 Phase 1 clinical trial. The award is paid based on developmental milestones, of which $19.7 million had been received as of December 31, 2021 with up to an aggregate of $0.1 million in future milestone payments. In the fourth quarter of 2021, the Company made the decision to wind down clinical development of the P-BCMA-101 program, which resulted in write off of the amount previously included in the deferred CIRM grant liability as the Company no longer intends to repay the award and is included in other income in the accompanying consolidated statement of operations.

In September 2018, the Company was granted an award in the amount of $4.0 million from CIRM to support the Company’s preclinical studies for its P-PSMA-101 program. The award is paid based on developmental milestones, of which the full $4.0 million had been received as of December 31, 2021.

Note 6. Collaborations and License Agreement with Takeda

In October 2021, the Company entered into a collaboration and license agreement (the “Takeda Collaboration Agreement”) with Takeda Pharmaceuticals USA, Inc. (“Takeda”), pursuant to which the Company granted to Takeda a worldwide exclusive license under the Company’s certain platform technologies including piggyBac, Cas-CLOVER, biodegradable DNA and RNA nanoparticle delivery technology and other proprietary genetic engineering platforms to research, develop, manufacture and commercialize gene therapy products for certain indications, including Hemophilia A. The parties are collaborating to initially develop up to six in vivo gene therapy programs and Takeda also has an option to add two additional programs to the collaboration. The Company is obligated to perform research activities to the extent requested by Takeda up to the candidate selection stage, after which Takeda is obligated to assume responsibility for further development, manufacturing and commercialization of each program.

Under the Takeda Collaboration Agreement, the Company received an upfront payment of $45.0 million, of which $5.0 million represents prepaid research funding. Takeda is obligated to provide funding for all collaboration program development costs; provided

that the Company is obligated to perform certain platform development activities at its own cost. Under the Takeda Collaboration Agreement, the Company is eligible to receive preclinical milestone payments that could potentially exceed $82.5 million in the aggregate if preclinical milestones for all six programs are achieved. The Company is also eligible to receive future clinical development, regulatory and commercial milestone payments of $435.0 million in the aggregate per target, with a total potential deal value over the course of the collaboration of up to $2.7 billion, if milestones for all six programs are achieved and up to $3.6 billion if the milestones related to the two optional programs are also achieved. The Company is entitled to receive tiered royalty payments on net sales in the mid-single to low double digits, subject to certain standard reductions and offsets. Royalties will be payable, on a product-by-product and country-by-country basis, until the latest of the expiration of the licensed patents covering such product in such country, ten years from first commercial sale of such product in such country, or expiration of regulatory exclusivity for such product in such country.

The promised goods and services under the Takeda Collaboration Agreement were accounted for as following separate performance obligations: (i) development and commercialization licenses for initial two indications, (ii) separate material rights associated with four additional licenses Takeda has an option to acquire individually, (iii) platform technology enhancement services, and (iv) research and development services.

In order to determine the transaction price, the Company evaluated all the payments to be received during the duration of the Takeda Collaboration Agreement. Certain milestones and additional fees were considered variable consideration, which were not included in the initial transaction price based on the most likely amount method. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The Company determined that the transaction price at the inception of the Takeda Collaboration Agreement consists of the upfront payment of $40.0  million and $5.0  million in prepaid research funding.

The Company allocated the transaction price to individual performance obligations on their relative standalone selling price basis. Standalone selling prices are based on observable prices at which the Company separately sells the products or services. If a standalone selling price is not directly observable, then the Company estimates the standalone selling price considering market conditions and entity-specific factors including, but not limited to, features and functionality of the products and services.

The performance obligation associated with the development and commercialization licenses for initial two indications was satisfied at the inception of the Takeda Collaboration Agreement. The separate material rights associated with additional licenses Takeda has an option to acquire individually are satisfied at a point in time in the future upon the earliest of Takeda exercising the option to acquire additional licenses or the expiration of the option. The platform technology enhancement services and the research and development services are satisfied over time as the Company performs the services for Takeda. The Company determined that the cost-based input method most faithfully depicts the pattern in which these performance obligations are satisfied. The Company recognizes revenue based on actual costs incurred as a percentage of total estimated costs as the Company completes its performance obligation under the Takeda Collaboration Agreement. Costs consist primarily of internal full-time employee (FTE) and certain reimbursable costs.

The Company recognized revenue for the combined performance obligation consisting of a development and commercialization license and platform technology enhancement services based on the amount of incurred development expenses reimbursed by the customer as a percentage of total expected reimbursable expenses associated with the contract. As of December 31, 2021, all future potential milestone payments were excluded from the estimated total transaction price as they were considered constrained.

For the year ended December 31, 2021, the Company recognized revenue of $31.2 million from the Takeda Collaboration Agreement, consisting of $30.2 million recognized at a point in time related to the development and commercialization licenses for the initial two indications, and $1.0 million recognized for the platform technology enhancement services and the research and development services, which are delivered over time. As of December 31, 2021, the balance of estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied, or partially unsatisfied, pursuant to the Company’s existing collaboration and license agreement consisted of $4.5 million presented as a deferred revenue, current and $9.3 million presented as a deferred revenue, non-current, in the accompanying consolidated balance sheet.