COMMITMENTS AND CONTINGENCIES	12 Months Ended
Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Proceedings From time to time, the Company has been and may again become involved in legal proceedings arising in the ordinary course of its business, including those related to patents, product liability and government investigations. Except as described below, the Company is not presently a party to any legal proceedings that it believes to be material, and is not aware of any pending or threatened litigation against the Company which it believes could have a material adverse effect on its business, operating results, financial condition or cash flows. MyoScience Milestone Litigation In August 2020, the Company and its subsidiary, Pacira CryoTech, Inc. (“Pacira CryoTech”), filed a lawsuit in the Court of Chancery of the State of Delaware against Fortis Advisors LLC (“Fortis”), solely in its capacity as representative for the former securityholders of MyoScience, and certain other defendants, seeking declaratory judgment with respect to certain terms of the merger agreement for the MyoScience Acquisition (the “MyoScience Merger Agreement”), specifically related to the achievement of certain milestone payments under the MyoScience Merger Agreement. In addition, the Company and Pacira CryoTech sought general, special and compensatory damages against the other defendants related to breach of fiduciary duties in connection with the purported achievement of milestone payments under the MyoScience Merger Agreement, and breach of the MyoScience Merger Agreement and certain other agreements with the defendants. In October 2020, Fortis filed an answer and counterclaim against the Company and Pacira CryoTech seeking to recover certain milestone payments under the MyoScience Merger Agreement. The total remaining value of these milestones is $30.0 million, plus attorneys’ fees. The Company believes that the counterclaim from Fortis is without merit and intends to vigorously defend against all claims. The Company is unable to predict the outcome of this action at this time. eVenus Pharmaceutical Laboratories Litigations In October 2021, the Company received a Notice Letter advising that eVenus Pharmaceutical Laboratories, Inc., or eVenus, of Princeton, New Jersey, submitted to the FDA an Abbreviated New Drug Application (ANDA) with a Paragraph IV certification seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (266 mg/20 mL) in the U.S. prior to the expiration of U.S. Patent No. 11,033,495 (the ’495 patent). In November 2021, the Company filed a patent infringement suit against eVenus and its parent company in the U.S. District Court for the District of New Jersey (21-cv-19829) asserting infringement of the ’495 patent. This triggered an automatic 30-month stay of final approval of the eVenus ANDA. On January 6, 2022, eVenus filed an Answer with counterclaims to the Complaint, alleging the ’495 patent is invalid and/or not infringed through the manufacture, sale, or offer for sale of the product described in product described in eVenus’s ANDA submission. In December 2021, the Company received a second Notice Letter advising that eVenus submitted to the FDA an amendment to its ANDA with a Paragraph IV Certification seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (133 mg/10 mL) in the U.S. prior to the expiration of the ’495 patent. In the Notice Letter, eVenus also advised that it submitted a Paragraph IV Certification to the FDA seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (266 mg/20 mL and 133 mg/10 mL) in the U.S. prior to the expiration of U.S. Patent No. 11,179,336 (the ’336 patent). eVenus further alleges in the Notice Letter that both the ’495 patent and the ’336 patent are invalid and/or not infringed. In February 2022, the Company filed a second patent infringement suit against eVenus and its parent company in the U.S. District Court for the District of New Jersey (22-cv-00718) asserting that the 133 mg/10 mL ANDA product will infringe the ’495 and ’336 patents and that the 266 mg/20 mL ANDA product will infringe the ’336 patent. This filing triggered a second automatic 30-month stay of final approval for the 133 mg/10 mL ANDA product. These litigations are in their early stages, and the Company is unable to predict their outcome at this time. Research Development Foundation Pursuant to an agreement with the Research Development Foundation, or RDF, the Company was required to pay RDF a low single-digit royalty on the collection of revenues from certain products, for as long as certain patents assigned to the Company under the agreement remain valid. RDF has the right to terminate the agreement for an uncured material breach by the Company, in connection with its bankruptcy or insolvency or if it directly or indirectly opposes or disputes the validity of the assigned patent rights. The Company’s ’495 patent issued on June 15, 2021. Thereafter, RDF asserted that the issuance of that patent extends the Company’s royalty obligations under the agreement until 2041. The Company believes that the royalty period under the agreement ended on December 24, 2021 with the expiration of its U.S. Patent No. 9,585,838. Because of the disagreement over the interpretation of the agreement, in December 2021, the Company filed a declaratory judgment lawsuit in the U.S. District Court for the District of Nevada (21-cv-02241). The lawsuit seeks a declaration from the court that the Company owes no royalties to RDF with respect to its EXPAREL product after December 24, 2021. During the pendency of the lawsuit, the Company will continue to pay royalties to RDF under protest, however, the Company is unable to predict the outcome of this action at this time. Purchase Obligations The Company has approximately $73.3 million of minimum, non-cancelable contractual commitments for contract manufacturing services and $5.2 million of minimum, non-cancelable contractual commitments for the purchase of certain raw materials as of December 31, 2022. Subsequent to December 31, 2022, the Company entered into an additional $2.8 million of minimum, non-cancelable contractual commitments for marketing sponsorships. Other Commitments and Contingencies Termination of License Agreement Prior to the Flexion Acquisition, in March 2020, Flexion entered into an exclusive license agreement with Hong Kong Tainuo Pharma Ltd., or HK Tainuo, and Jiangsu Tainuo Pharmaceutical Co. Ltd., a subsidiary of China Shijiazhuang Pharmaceutical Co, Ltd., for the development and commercialization of ZILRETTA in Greater China (consisting of mainland China, Hong Kong, Macau and Taiwan). Under the terms of the agreement, HK Tainuo paid Flexion an upfront payment of $10.0 million during the year ended December 31, 2020 which was recorded as deferred revenue as of December 31, 2021. The Company was also eligible to receive up to $32.5 million in aggregate development, regulatory and commercial sales milestone payments under the exclusive license agreement. HK Tainuo was responsible for the clinical development, product registration and commercialization of ZILRETTA in Greater China. The Company was solely responsible for the manufacture and supply of ZILRETTA to HK Tainuo for all clinical and commercial activities. The terms related to product manufacturing and supply, including pricing and minimum purchase requirements agreed to in the license agreement, were to be covered by a separate supply agreement which was never finalized. In July 2022, the Company submitted notice to HK Tainuo of its intent to pursue termination of the license agreement. As of December 31, 2022, $13.0 million was recorded within accrued expenses in the consolidated balance sheet. The $13.0 million related to the termination of the license agreement was subsequently paid in January 2023. Pediatric Trial Commitments The FDA, as a condition of EXPAREL approval, has required the Company to study EXPAREL in pediatric patients, as well as the administration of EXPAREL as a nerve block in the pediatric setting. The Company was granted a deferral for the required pediatric trials until after the indications were approved in adults. Similarly, in Europe, the Company agreed with the European Medicines Agency, or EMA, on a Pediatric Investigation Plan as a prerequisite for submitting a Marketing Authorization Application (MAA) in the E.U. Despite the U.K.’s withdrawal from the E.U., the agreed pediatric plan is applicable in the U.K. In December 2019, the Company announced positive results for its extended pharmacokinetic and safety study (“PLAY”) for local analgesia in children aged six to 17 undergoing cardiovascular or spine surgeries. Those positive results were the basis for the submission of a supplemental New Drug Application, or sNDA, in the U.S. and Type II variations in the E.U. and U.K. to expand the EXPAREL label to include use in patients six years of age and older for single-dose infiltration to produce postsurgical local analgesia. In March 2021, the Company announced that the FDA approved the submission of the sNDA in the U.S. The EMA and the Medicines and Healthcare Products Regulatory Agency, or MHRA, are still reviewing the Type II variations. The Company is working with the FDA, MAA and MHRA to finalize the regulatory pathway for its remaining pediatric commitments. Contingent Milestone Payments Refer to Note 5, Flexion Acquisition and Note 12, Financial Instruments, for information on potential contingent milestone payments related to the Flexion Acquisition and MyoScience Acquisition. PCRX-201 PCRX-201 was added to the Company’s portfolio as part of the Flexion Acquisition as discussed in Note 5, Flexion Acquisition. Prior to the Flexion Acquisition, in February 2017, Flexion entered into an agreement with GQ Bio Therapeutics GmbH (formerly named GeneQuine Biotherapeutics GmbH) to acquire the global rights to PCRX-201, a gene therapy product candidate. As part of the agreement, up to an aggregate of $56.0 million of payments could become due upon the achievement of certain development and regulatory milestones, including up to $4.5 million through initiation of a Phase 2 proof of concept clinical trial and, following successful proof of concept, up to an additional $51.5 million in development and global regulatory approval milestone payments.

From time to time, the Company has been and may again become involved in legal proceedings arising in the ordinary course of its business, including those related to patents, product liability and government investigations. Except as described below, the Company is not presently a party to any legal proceedings that it believes to be material, and is not aware of any pending or threatened litigation against the Company which it believes could have a material adverse effect on its business, operating results, financial condition or cash flows.

In August 2020, the Company and its subsidiary, Pacira CryoTech, Inc. (“Pacira CryoTech”), filed a lawsuit in the Court of Chancery of the State of Delaware against Fortis Advisors LLC (“Fortis”), solely in its capacity as representative for the former securityholders of MyoScience, and certain other defendants, seeking declaratory judgment with respect to certain terms of the merger agreement for the MyoScience Acquisition (the “MyoScience Merger Agreement”), specifically related to the achievement of certain milestone payments under the MyoScience Merger Agreement. In addition, the Company and Pacira CryoTech sought general, special and compensatory damages against the other defendants related to breach of fiduciary duties in connection with the purported achievement of milestone payments under the MyoScience Merger Agreement, and breach of the MyoScience Merger Agreement and certain other agreements with the defendants. In October 2020, Fortis filed an answer and counterclaim against the Company and Pacira CryoTech seeking to recover certain milestone payments under the MyoScience Merger Agreement. The total remaining value of these milestones is $30.0 million, plus attorneys’ fees. The Company believes that the counterclaim from Fortis is without merit and intends to vigorously defend against all claims. The Company is unable to predict the outcome of this action at this time.

In October 2021, the Company received a Notice Letter advising that eVenus Pharmaceutical Laboratories, Inc., or eVenus, of Princeton, New Jersey, submitted to the FDA an Abbreviated New Drug Application (ANDA) with a Paragraph IV certification seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (266 mg/20 mL) in the U.S. prior to the expiration of U.S. Patent No. 11,033,495 (the ’495 patent).

In November 2021, the Company filed a patent infringement suit against eVenus and its parent company in the U.S. District Court for the District of New Jersey (21-cv-19829) asserting infringement of the ’495 patent. This triggered an automatic 30-month stay of final approval of the eVenus ANDA. On January 6, 2022, eVenus filed an Answer with counterclaims to the Complaint, alleging the ’495 patent is invalid and/or not infringed through the manufacture, sale, or offer for sale of the product described in product described in eVenus’s ANDA submission.

In December 2021, the Company received a second Notice Letter advising that eVenus submitted to the FDA an amendment to its ANDA with a Paragraph IV Certification seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (133 mg/10 mL) in the U.S. prior to the expiration of the ’495 patent. In the Notice Letter, eVenus also advised that it submitted a Paragraph IV Certification to the FDA seeking authorization for the manufacturing and marketing of a generic version of EXPAREL (266 mg/20 mL and 133 mg/10 mL) in the U.S. prior to the expiration of U.S. Patent No. 11,179,336 (the ’336 patent). eVenus further alleges in the Notice Letter that both the ’495 patent and the ’336 patent are invalid and/or not infringed.

In February 2022, the Company filed a second patent infringement suit against eVenus and its parent company in the U.S. District Court for the District of New Jersey (22-cv-00718) asserting that the 133 mg/10 mL ANDA product will infringe the ’495 and ’336 patents and that the 266 mg/20 mL ANDA product will infringe the ’336 patent. This filing triggered a second automatic 30-month stay of final approval for the 133 mg/10 mL ANDA product.

Pursuant to an agreement with the Research Development Foundation, or RDF, the Company was required to pay RDF a low single-digit royalty on the collection of revenues from certain products, for as long as certain patents assigned to the Company under the agreement remain valid. RDF has the right to terminate the agreement for an uncured material breach by the Company, in connection with its bankruptcy or insolvency or if it directly or indirectly opposes or disputes the validity of the assigned patent rights. The Company’s ’495 patent issued on June 15, 2021. Thereafter, RDF asserted that the issuance of that patent extends the Company’s royalty obligations under the agreement until 2041. The Company believes that the royalty period under the agreement ended on December 24, 2021 with the expiration of its U.S. Patent No. 9,585,838. Because of the disagreement over the interpretation of the agreement, in December 2021, the Company filed a declaratory judgment lawsuit in the U.S. District Court for the District of Nevada (21-cv-02241). The lawsuit seeks a declaration from the court that the Company owes no royalties to RDF with respect to its EXPAREL product after December 24, 2021. During the pendency of the lawsuit, the Company will continue to pay royalties to RDF under protest, however, the Company is unable to predict the outcome of this action at this time.

The Company has approximately $73.3 million of minimum, non-cancelable contractual commitments for contract manufacturing services and $5.2 million of minimum, non-cancelable contractual commitments for the purchase of certain raw materials as of December 31, 2022. Subsequent to December 31, 2022, the Company entered into an additional $2.8 million of minimum, non-cancelable contractual commitments for marketing sponsorships.

Prior to the Flexion Acquisition, in March 2020, Flexion entered into an exclusive license agreement with Hong Kong Tainuo Pharma Ltd., or HK Tainuo, and Jiangsu Tainuo Pharmaceutical Co. Ltd., a subsidiary of China Shijiazhuang Pharmaceutical Co, Ltd., for the development and commercialization of ZILRETTA in Greater China (consisting of mainland China, Hong Kong, Macau and Taiwan). Under the terms of the agreement, HK Tainuo paid Flexion an upfront payment of $10.0 million during the year ended December 31, 2020 which was recorded as deferred revenue as of December 31, 2021. The Company was also eligible to receive up to $32.5 million in aggregate development, regulatory and commercial sales milestone payments under the exclusive license agreement. HK Tainuo was responsible for the clinical development, product registration and commercialization of ZILRETTA in Greater China. The Company was solely responsible for the manufacture and supply of ZILRETTA to HK Tainuo for all clinical and commercial activities. The terms related to product manufacturing and supply, including pricing and minimum purchase requirements agreed to in the license agreement, were to be covered by a separate supply agreement which was never finalized.

In July 2022, the Company submitted notice to HK Tainuo of its intent to pursue termination of the license agreement. As of December 31, 2022, $13.0 million was recorded within accrued expenses in the consolidated balance sheet. The $13.0 million related to the termination of the license agreement was subsequently paid in January 2023.

The FDA, as a condition of EXPAREL approval, has required the Company to study EXPAREL in pediatric patients, as well as the administration of EXPAREL as a nerve block in the pediatric setting. The Company was granted a deferral for the required pediatric trials until after the indications were approved in adults. Similarly, in Europe, the Company agreed with the European Medicines Agency, or EMA, on a Pediatric Investigation Plan as a prerequisite for submitting a Marketing Authorization Application (MAA) in the E.U. Despite the U.K.’s withdrawal from the E.U., the agreed pediatric plan is applicable in the U.K.

In December 2019, the Company announced positive results for its extended pharmacokinetic and safety study (“PLAY”) for local analgesia in children aged six to 17 undergoing cardiovascular or spine surgeries. Those positive results were the basis for the submission of a supplemental New Drug Application, or sNDA, in the U.S. and Type II variations in the E.U. and U.K. to expand the EXPAREL label to include use in patients six years of age and older for single-dose infiltration to produce postsurgical local analgesia. In March 2021, the Company announced that the FDA approved the submission of the sNDA in the U.S. The EMA and the Medicines and Healthcare Products Regulatory Agency, or MHRA, are still reviewing the Type II variations. The Company is working with the FDA, MAA and MHRA to finalize the regulatory pathway for its remaining pediatric commitments.

PCRX-201 was added to the Company’s portfolio as part of the Flexion Acquisition as discussed in Note 5, Flexion Acquisition. Prior to the Flexion Acquisition, in February 2017, Flexion entered into an agreement with GQ Bio Therapeutics GmbH (formerly named GeneQuine Biotherapeutics GmbH) to acquire the global rights to PCRX-201, a gene therapy product candidate. As part of the agreement, up to an aggregate of $56.0 million of payments could become due upon the achievement of certain development and regulatory milestones, including up to $4.5 million through initiation of a Phase 2 proof of concept clinical trial and, following successful proof of concept, up to an additional $51.5 million in development and global regulatory approval milestone payments.