RX PERSPECTIVE

Preventing intraoperative miosis

Omeros’ Omidria irrigating solution provides benefits for cataract surgery and lens replacement patients.

By Steven M. Silverstein MD, FACS

Ideally, surgeons should be capable of identifying patients at highest risk for intraoperative miosis or significant postoperative pain. Although this is sometimes the case, the reality is that we cannot always do so consistently.

In May 2014, Omidria (Omeros Corporation) received FDA approval as an additive to irrigating solution during cataract surgery and lens replacement procedures, indicated for maintaining pupil size by preventing intraoperative miosis and reducing postoperative ocular pain.

PRODUCT OVERVIEW

Omidria, a combination agent, recently launched in the United States. The product consists of an alpha 1-adrenergic receptor agonist (1% phenylephrine) and a nonselective cyclooxygenase inhibitor (0.3% ketorolac), which is preservative- and bisulfite-free. One single-use vial (4 ml) is added pre-operatively to a 500 cc bottle of irrigating solution.

Last fall, CMS designated Omidria as a pass-through product, which makes this solution particularly novel. Pass-through products are billed separately and not bundled into the physician nor facility procedure reimbursement.

MY EXPERIENCE

My first exposure to this product occurred several years ago at its earliest clinical trial. During the trial, I found the protocol was particularly thorough, requiring video-taped procedures under strict parameters, for purposes of making careful pupil size measurements pre- and intra-operatively, and employing a validated rating scale pertaining to post-operative pain. Inclusion/exclusion criteria were tight, and the study was monitored closely. Though the surgeon was masked to those patients who received active ingredient vs. placebo, some patients enjoyed very stable mydriasis, while others behaved as we typically experience on an average surgery day.

Studies confirmed the early findings and demonstrated for the FDA a statistically significant reduction in postoperative pain. More than five times as many patients in the placebo groups experienced a pupil diameter of less than 6 mm during the procedure compared to the Omidria groups. Adverse events were low and similar in both type and frequency to those reported for the placebo groups. In a pharmacokinetic study evaluating Omidria, systemic exposure to both phenylephrine and ketorolac was low or undetectable.

REIMBURSEMENT

Effective Jan. 1, 2015, CMS assigned Omidria a unique billing code (C9447) within the national OPPS payment schedule for facilities (HOPD or ASC).

Omidria was granted separate payment or “pass-through” status by CMS, which means the product is reimbursed by CMS outside of the bundled payment for cataract surgery. Medicare reimburses the wholesale acquisition cost ($465) for Omidria plus 6% per single-use vial. At present, the surgeon receives no separate or distinct professional service fee because irrigation use in the eye during cataract surgery is an inherent part of the procedure.

IS IT NECESSARY?

This product would likely not suffer the shortages we experienced recently with epinephrine. In addition, the benefits in reducing postoperative pain and inflammation with the topical use of NSAIDs, including ketorolac, have been well studied and reported. It stands to reason that the introduction of ketorolac inside the eye at the time of surgery and at the site of the surgical trauma, which creates inflammation and its sequelae, would benefit the patient.

Remember that ketorolac is also contributing to the maintenance of intraoperative pupil diameter. In the Phase 2b clinical trial in which all patients received standard preoperative topical mydriatics and anesthetics, Omidria in the irrigation solution was compared directly to phenylephrine in the irrigation solution. Only 6% of the Omidria-treated patients vs. 22% of the phenylephrine-treated patients demonstrated intraoperative pupil diameters less than 6 mm (P=0.0221).

I would expect this difference to hold for epinephrine given that phenylephrine is an alpha-1-selective adrenergic agonist while epinephrine is an alpha and beta nonselective adrenergic agonist. Efficacy and safety of Omidria were confirmed in Phase 3 clinical trials.

My personal experience with Omidria, following its recent market launch, has been only positive. I have used the product with femtosecond laser surgeries, in routine cases, and in IFIS and pseudoexfoliation patients. I have not had to use mechanical dilating devices in any cases in which I have used Omidria. In addition, my facility has received full reimbursement for each case in which Omidria was used. OM

Steven M. Silverstein, MD, FACS, is a cornea-trained comprehensive ophthalmologist in practice at Silverstein Eye Centers in Kansas City, Mo. His e-mail is ssilverstein@silversteineyecenters.com.