A Phase 4 interventional study of Adjunct Exparel (bupivacaine liposome suspension 1.3%) and Standard Care in Tonsillectomy, sponsored by Paul Hoff. Completed at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Paul Hoff · Phase 4, Interventional, and Treatment
Tonsillectomy is one of the most commonly performed surgical procedures in the United States. The primary indications for tonsillectomy in the adult population include recurrent pharyngitis, chronic tonsillitis, and obstructive pathology. Tonsillectomy is often associated with severe postoperative pain, which can result in prolonged poor oral intake, dehydration, and the need for high dose narcotics. In severely dehydrated patients, epithelial shedding and necrosis of soft tissues at the surgical site can lead to postoperative complications such as bleeding, delayed healing, and severe pain. The goal for this study is to explore the use of a long acting local anesthetic bupivacaine liposome injectable suspension (Exparel) to manage pain experienced by adult patients after tonsillectomy
The proposed investigation will examine whether Exparel (bupivacaine liposome injectable suspension 1.3%-13.3 mg/mL) when used as a post-excision adjunct to the standard of care bupivacaine HCl 0.25% (2.5 mg/mL) with Epinephrine (5mcg/mL), will decrease the patient's post-tonsillectomy experience of pain intensity, especially for the first three days after surgery, and correspondingly reduce the requirement for pain medications and improve outcomes.
10,054 studies on the registry are indexed under Pain; 1,649 are open to participants now.
This study's enrollment of 42 is below the median of 66 across 8,493 interventional studies indexed under Pain.
Browse Pain studies →This is the only study on the registry with Paul Hoff as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
After removal of the tonsils and before extubation, the principal investigator will infiltrate 0.5 mL of the standard of care medication-bupivacaine HCl 0.25% (2.5 mg/mL) with epinephrine (5 mcg/mL) i.m.-into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine HCl on each side. Following the standard medication, the principal investigator will infiltrate 0.5 mL of adjunct Exparel (bupivacaine liposome suspension 1.3% \[13.3 mg/mL\], i.m.) into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine liposome injectable suspension on each side.
Drug: Adjunct Exparel (bupivacaine liposome suspension 1.3%) · Other: Standard Care
After removal of the tonsils and before extubation, the principal investigator will infiltrate 0.5 mL of the standard of care medication-bupivacaine HCl 0.25% (2.5 mg/ mL) with epinephrine (5 mcg/mL) i.m.-into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine HCl on each side.
Other: Standard Care
After removal of the tonsils and before extubation, the principal investigator will infiltrate 0.5 mL of the standard of care medication-bupivacaine HCl 0.25% (2.5 mg/mL) with epinephrine (5 mcg/mL) i.m.-into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine HCl on each side. Following the standard medication, the principal investigator will infiltrate 0.5 mL of adjunct Exparel (bupivacaine liposome suspension 1.3% \[13.3 mg/mL\] i.m.) into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine liposome injectable suspension 1.3% (13.3 mg/mL) on each side.
Also known as: Bupivacaine liposome suspension 1.3%
After removal of the tonsils and before extubation, the principal investigator will infiltrate 0.5 mL of the standard of care medication-bupivacaine HCl 0.25% (2.5 mg/ mL) with epinephrine (5 mcg/mL) i.m.-into the upper and lower poles of the anterior and posterior tonsillar pillars on the right and left side of the oropharynx for a volume of 2 mL of bupivacaine HCl on each side.
Also known as: Bupivacaine HCl with epinephrine
Pain Rating Between Post Anesthesia Care Unit (PACU) Baseline and Designated Post-operative Days
Patient reported average and maximum pain rating over a 24-hour period using the St. Joseph Mercy Ann Arbor (SJMAA) standard visual analog 11-point pain rating scale. The minimum value of 0 indicates no pain and the maximum value of 10 indicates the worst possible pain. A higher value represents greater pain and a worse outcome. The baseline pain rating is the maximum rating from PACU on the day of surgery. Day-1 begins at 12:00 AM (after midnight) day of surgery and extends through 11:59 PM. Each following designated day will begin at 12:00 AM and extend through 11:59 PM. We calculated delta mean pain scores by subtracting the mean pain score of Post Operative Day (POD) 2, 3, 5, and 10 from the mean pain score of POD 1, respectively.
Time frame: Post-tonsillectomy Days 1, 2, 3, 5, and 10
Patients Taking Prescribed Narcotic Pain Medication Between Day-1 and Designated Post-operative Days
Number of patients who reported use of prescribed narcotic pain medication in 24 hours. Day-1 begins at 12:00 AM (midnight after the day of surgery and extends through 11:59 PM. Day-2 and each following designated day will begin at 12:00 AM and will extend through 11:59 PM.
Time frame: Post-tonsillectomy Days 1, 2, 3, 5, and 10
| Milestone | Adjunct Exparel | Standard Care |
|---|---|---|
| Started | 22 | 20 |
| Completed | 22 | 20 |
| Not completed | 0 | 0 |
Patient reported average and maximum pain rating over a 24-hour period using the St. Joseph Mercy Ann Arbor (SJMAA) standard visual analog 11-point pain rating scale. The minimum value of 0 indicates no pain and the maximum value of 10 indicates the worst possible pain. A higher value represents greater pain and a worse outcome. The baseline pain rating is the maximum rating from PACU on the day of surgery. Day-1 begins at 12:00 AM (after midnight) day of surgery and extends through 11:59 PM. Each following designated day will begin at 12:00 AM and extend through 11:59 PM. We calculated delta mean pain scores by subtracting the mean pain score of Post Operative Day (POD) 2, 3, 5, and 10 from the mean pain score of POD 1, respectively.
| score on a scale | Adjunct Exparel | Standard Care |
|---|---|---|
| POD2-POD1 Pain Score | -0.12 ± 0.96 | -0.26 ± 1.24 |
| POD3-POD1 Pain score | 0.50 ± 1.37 | -0.39 ± 1.14 |
| POD5-POD1 Pain score | -0.27 ± 1.39 | -0.72 ± 1.84 |
| POD10-POD1 Pain score | 2.81 ± 1.87 | 2.50 ± 1.82 |
Number of patients who reported use of prescribed narcotic pain medication in 24 hours. Day-1 begins at 12:00 AM (midnight after the day of surgery and extends through 11:59 PM. Day-2 and each following designated day will begin at 12:00 AM and will extend through 11:59 PM.
| percentage of participants | Adjunct Exparel | Standard Care |
|---|---|---|
| Oxycodone POD1 | 100 | 94.7 |
| Oxycodone POD2 | 100 | 94.4 |
| Oxycodone POD3 | 100 | 88.9 |
| Oxycodone POD5 | 68.8 | 61.1 |
| Oxycodone POD10 | 18.8 | 11.1 |
Collected over Adverse event data were collected postoperatively on days 1, 2, 3, 5, and 10.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Adjunct Exparel | 0/22 (0%) | 0/22 (0%) | 0/22 (0%) |
| Standard Care | 0/20 (0%) | 0/20 (0%) | 0/20 (0%) |
| Age, Continuous(Years) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| Mean | 27.95 (18 to 47) | 32 (20 to 69) | 29.88 (18 to 69) |
| Sex: Female, Male(Participants) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| Female | 13 | 18 | 31 |
| Male | 9 | 2 | 11 |
| Ethnicity (NIH/OMB)(Participants) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| Hispanic or Latino | 1 | 0 | 1 |
| Not Hispanic or Latino | 20 | 17 | 37 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 1 | 4 | 5 |
| White | 21 | 15 | 36 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Systolic Blood Pressure(mmHg) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| Mean | 126.04 ± 12.97 | 117.45 ± 11.83 | 122.3 ± 13.08 |
| Diastolic Blood Pressure(mmHg) | Adjunct Exparel | Standard Care | Total |
|---|---|---|---|
| Mean | 79.12 ± 10.66 | 74.95 ± 8.92 | 77.3 ± 10.05 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Feb 2018 to primary completion in Dec 2022, 58 months.
Results were first posted in Oct 2026, 3 years 9 months after primary completion.
Of 280 non-industry phase 4 interventional studies under Pain, half reached primary completion within 18 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 35. This study's 58 months is above that.
Counting every sponsor, half of 295 studies reached it within 18 months; a quarter within 8 and three quarters within 33.
Since we started tracking on Sep 25, 2026, the dates moved once, on Oct 30, 2026: primary completion Dec 2021 → Dec 2022 and completion Dec 2021 → Dec 2022.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.