Business	6 Months Ended
Jun. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Business	1. Business We are a commercial-stage biotechnology company focused on improving the lives of patients by developing best-in-class treatments to address some of the most important unmet patient needs. We are developing novel, patient-focused solutions that apply our innovative science and technologies to already-approved pharmacological agents for patients suffering from pain or cancer. On August 9, 2016, our first commercial product, SUSTOL (granisetron) extended-release injection (“SUSTOL”), was approved by the U.S. Food and Drug Administration (“FDA”). SUSTOL is indicated in combination with other antiemetics in adults for the prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic chemotherapy (MEC) or anthracycline and cyclophosphamide (AC) combination chemotherapy regimens. SUSTOL is an extended-release, injectable 5-hydroxytryptamine type 3 receptor antagonist that utilizes Heron’s proprietary Biochronomer drug delivery technology (“Biochronomer Technology”) to maintain therapeutic levels of granisetron for ≥5 days. We commenced commercial sales of SUSTOL in the U.S. in October 2016. On November 9, 2017, our second commercial product, CINVANTI (aprepitant) injectable emulsion (“CINVANTI”), was approved by the FDA. CINVANTI, in combination with other antiemetic agents, is indicated in adults for the prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin and nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). CINVANTI is an intravenous (“IV”) formulation of aprepitant, a substance P/neurokinin-1 (“NK₁”) receptor antagonist. CINVANTI is the only IV formulation of an NK₁ receptor antagonist indicated for the prevention of acute and delayed nausea and vomiting associated with HEC and nausea and vomiting associated with MEC that is free of polysorbate 80 or any other synthetic surfactant. We commenced commercial sales of CINVANTI in the U.S. in January 2018. On February 26, 2019, we announced that the FDA approved our supplemental New Drug Application (“sNDA”) for CINVANTI, for IV use, which expanded the administration of CINVANTI beyond the initially approved administration method (a 30-minute IV infusion) to include a 2-minute IV injection. HTX-011, which utilizes Heron’s proprietary Biochronomer Technology, is an investigational, long-acting, extended-release formulation of the local anesthetic bupivacaine in a fixed-dose combination with the anti-inflammatory meloxicam for postoperative pain management. By delivering sustained levels of both a potent anesthetic and a local anti-inflammatory agent directly to the site of tissue injury, HTX-011 was designed to deliver superior pain relief while reducing the need for systemically administered pain medications such as opioids, which carry the risk of harmful side effects, abuse and addiction. HTX-011 has been shown to reduce pain significantly better than placebo or bupivacaine alone in five diverse surgical models: hernia repair, abdominoplasty, bunionectomy, total knee arthroplasty and breast augmentation. HTX-011 was granted Fast Track designation from the FDA in the fourth quarter of 2017 and Breakthrough Therapy designation in the second quarter of 2018. We submitted a New Drug Application (“NDA”) for HTX-011 to the FDA in October of 2018 and received Priority Review designation in December of 2018. A Complete Response Letter (“CRL”) was received from the FDA regarding the NDA for HTX-011 on April 30, 2019. The CRL stated that the FDA was unable to approve the NDA in its present form based on the need for additional Chemistry, Manufacturing and Controls (“CMC”) and non-clinical information. Based on the complete review of the NDA, the FDA did not identify any clinical safety or efficacy issues, and there was no requirement for further clinical studies or data analyses. In April 2019, we announced that the Marketing Authorisation Application (“MAA”) for HTX-011 was validated by the European Medicines Agency (“EMA”). Validation of the MAA confirms that the submission is complete and starts the EMA's Centralised Procedure. The EMA granted eligibility to the Centralised Procedure for HTX-011 based on it meeting the criteria of a medicinal product constituting a significant scientific innovation. The Centralised Procedure allows applicants to receive a marketing authorisation that is valid throughout the European Union. An opinion from the EMA Committee for Medicinal Products for Human Use (CHMP) is anticipated in the first half of 2020. HTX-034, our next generation product candidate for postoperative pain management, is in development for postoperative pain via local application. Based on the positive results of preclinical studies in which HTX-034 demonstrated significant pain reduction for seven days, we have initiated formal development of this next-generation postoperative pain management product candidate. As of June 30, 2019 we had $276.0 million in cash, cash equivalents and short-term investments. We have incurred significant operating losses and negative cash flows from operations. Management believes that cash, cash equivalents and short-term investments as of June 30, 2019 will be sufficient to fund operations for at least one year from the date this Quarterly Report on Form 10-Q is filed with the U.S. Securities and Exchange Commission (“SEC”).

Business

6 Months Ended

Jun. 30, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. Business

We are a commercial-stage biotechnology company focused on improving the lives of patients by developing best-in-class treatments to address some of the most important unmet patient needs. We are developing novel, patient-focused solutions that apply our innovative science and technologies to already-approved pharmacological agents for patients suffering from pain or cancer.

On August 9, 2016, our first commercial product, SUSTOL (granisetron) extended-release injection (“SUSTOL”), was approved by the U.S. Food and Drug Administration (“FDA”). SUSTOL is indicated in combination with other antiemetics in adults for the prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic chemotherapy (MEC) or anthracycline and cyclophosphamide (AC) combination chemotherapy regimens. SUSTOL is an extended-release, injectable 5-hydroxytryptamine type 3 receptor antagonist that utilizes Heron’s proprietary Biochronomer drug delivery technology (“Biochronomer Technology”) to maintain therapeutic levels of granisetron for ≥5 days. We commenced commercial sales of SUSTOL in the U.S. in October 2016.

On November 9, 2017, our second commercial product, CINVANTI (aprepitant) injectable emulsion (“CINVANTI”), was approved by the FDA. CINVANTI, in combination with other antiemetic agents, is indicated in adults for the prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin and nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). CINVANTI is an intravenous (“IV”) formulation of aprepitant, a substance P/neurokinin-1 (“NK₁”) receptor antagonist. CINVANTI is the only IV formulation of an NK₁ receptor antagonist indicated for the prevention of acute and delayed nausea and vomiting associated with HEC and nausea and vomiting associated with MEC that is free of polysorbate 80 or any other synthetic surfactant. We commenced commercial sales of CINVANTI in the U.S. in January 2018. On February 26, 2019, we announced that the FDA approved our supplemental New Drug Application (“sNDA”) for CINVANTI, for IV use, which expanded the administration of CINVANTI beyond the initially approved administration method (a 30-minute IV infusion) to include a 2-minute IV injection.

HTX-011, which utilizes Heron’s proprietary Biochronomer Technology, is an investigational, long-acting, extended-release formulation of the local anesthetic bupivacaine in a fixed-dose combination with the anti-inflammatory meloxicam for postoperative pain management. By delivering sustained levels of both a potent anesthetic and a local anti-inflammatory agent directly to the site of tissue injury, HTX-011 was designed to deliver superior pain relief while reducing the need for systemically administered pain medications such as opioids, which carry the risk of harmful side effects, abuse and addiction. HTX-011 has been shown to reduce pain significantly better than placebo or bupivacaine alone in five diverse surgical models: hernia repair, abdominoplasty, bunionectomy, total knee arthroplasty and breast augmentation. HTX-011 was granted Fast Track designation from the FDA in the fourth quarter of 2017 and Breakthrough Therapy designation in the second quarter of 2018. We submitted a New Drug Application (“NDA”) for HTX-011 to the FDA in October of 2018 and received Priority Review designation in December of 2018. A Complete Response Letter (“CRL”) was received from the FDA regarding the NDA for HTX-011 on April 30, 2019. The CRL stated that the FDA was unable to approve the NDA in its present form based on the need for additional Chemistry, Manufacturing and Controls (“CMC”) and non-clinical information. Based on the complete review of the NDA, the FDA did not identify any clinical safety or efficacy issues, and there was no requirement for further clinical studies or data analyses. In April 2019, we announced that the Marketing Authorisation Application (“MAA”) for HTX-011 was validated by the European Medicines Agency (“EMA”). Validation of the MAA confirms that the submission is complete and starts the EMA's Centralised Procedure. The EMA granted eligibility to the Centralised Procedure for HTX-011 based on it meeting the criteria of a medicinal product constituting a significant scientific innovation. The Centralised Procedure allows applicants to receive a marketing authorisation that is valid throughout the European Union. An opinion from the EMA Committee for Medicinal Products for Human Use (CHMP) is anticipated in the first half of 2020.

HTX-034, our next generation product candidate for postoperative pain management, is in development for postoperative pain via local application. Based on the positive results of preclinical studies in which HTX-034 demonstrated significant pain reduction for seven days, we have initiated formal development of this next-generation postoperative pain management product candidate.

As of June 30, 2019 we had $276.0 million in cash, cash equivalents and short-term investments. We have incurred significant operating losses and negative cash flows from operations. Management believes that cash, cash equivalents and short-term investments as of June 30, 2019 will be sufficient to fund operations for at least one year from the date this Quarterly Report on Form 10-Q is filed with the U.S. Securities and Exchange Commission (“SEC”).