By Annette M. Boyle
BETHESDA, MD — With increasing shortages of critical chemotherapy drugs – and the funds to buy them – VA pharmacists are constantly looking for ways to enable the medications and money to go farther so that more patients can be treated.
That is exactly what pharmacists at Walter Reed National Military Medical Center (WRNMMC) were able to do by using a closed system transfer device (CSTD) in a working pharmacy environment.
The WRNMMC Hematology-Oncology Pharmacy Service found that the PhaSeal closed system transfer device (CSTD) safely salvaged medication remaining in single-use vials of antineoplastic drugs and saved $96,348 in 50 days, for an annualized savings of more than $703,000, according to a study recently published in the Journal of Oncology Pharmacy Practice.1
The United States Pharmacopeia (USP) chapter 797 calls for sterile products packaged as single-use vials to be discarded after six hours if kept in an ISO 5 environment or after one hour if not kept under ISO 5 conditions. As a result, significant amounts of expensive and often hard to obtain drugs are simply thrown away. While the language of USP chapter 797 implies that multiple uses of these vials during the established time frame is permitted, prior to the study, the oncology pharmacy at Walter Reed discarded all unpreserved vials immediately after opening.
“A number of other studies showed that, by using the device, you could maintain sterility of single-use vials for up to seven days and safely use them multiple times,” said Michael S. Edwards, PharmD, director, oncology pharmacy residency, WRNMMC. “We wanted to see what cost savings were associated with not having to throw away the vials after one use.”
In September 2012, the FDA cleared the BD PhaSeal System to prevent microbial ingress for up to 168 hours – for up to 10 penetrations, in an ISO Class V or greater environment and with appropriate technique.
Salvaged 29% of Each Vial
For the study, the pharmacy compiled a list of 25 drugs that came in single-use vials and had chemical stability of at least 48 hours, then tracked their use over a 50-day period from April 30 through June 18, 2012. All parenteral products were prepared in ISO 5 conditions using Class II, Type 2 biological safety cabinets (BSC) and employing equipment mandated by USP 797 for personal protection.
During the study period, the pharmacists recorded use of 296 vials of 21 antineoplastic agents. The pharmacy retained all partially used vials and used them when possible to prepare subsequent doses within the two- to seven-day stability period.
Following the initial use, 57% of the medication remained in the vials, on average. Reuse of the vials enabled the pharmacy to save a mean of 29% of each vial.
“We only saved about half of drug remaining and threw out about half. We would have saved much more if we had had more of a chance to use it,” Edwards said. WRNMMC prepares 52 parenteral doses per day or more than 13,000 per year on average.
“While our study shows a $700,000 savings in drugs, we could save more as we get better at it. Bigger places, such as large cancer centers or the VA, could save even more, because we had to throw away vials we couldn’t finish in seven days, and they would have more patients who needed the drugs,” Edwards added.
Savings would also have been greater if the study protocol continued in effect, as all drugs remaining in opened vials at the end of the study were considered expired, even if they were still in the seven-day usage period. The authors estimated that usage of the remaining non-expired drugs in subsequent days would have increased the annual savings by $11,376. In addition, four of the drugs identified as eligible for the study were not prescribed during the period, but had dosing schedules that would have permitted salvage of partially used vials.
The authors noted that including monoclonal antibodies such as bevacizumab, cetuximab and rituximab would enable further savings. They estimated that adding these drugs to the study would have produced an annualized savings of $44,922 to $283,696, depending on the size of the vials used.
The authors added that extending the beyond-use date (BUD) using the PhaSeal device could help institutions extend the use of parenteral agents available as unpreserved solutions or powder for reconstitution that are on the American Society of Health-System Pharmacists’ list of drugs experiencing shortages.
“When I presented our results at a short research session at the Hemotology/Oncology Pharmacy Association meeting this year, a number of people asked questions about using the drugs for the extended period. Not everybody wants to believe the data,” Edwards said.
Previous studies published in the American Journal of Pharmacy Benefits showed 98% to 99.7% sterility of agents in single-use vials at 168 hours using a CTSD. Earlier this year, the Food and Drug Administration issued additional clearance for the PhaSeal system to be marketed for prevention of microbial ingress for up to 168 hours when used according to manufacturer’s instructions. The device was initially approved for use to prevent exposure of healthcare workers to hazardous drugs. 2,3
To prove that a working pharmacy could reproduce the results seen in the published research, Edwards is developing a study to assess the sterility of single-use vials using a CTSD for extended periods. “The seven-day sterility is not the same as the USP standards. Anybody using it has to prove that they are doing a good job managing the process, so we’re going to piggyback on the existing research and close the loop here,” he added.
1 Edwards MS, Solimando DA, Grollman FR, Pang JL, Chasick AH, et al. Cost savings realized by the use of the PhaSeal closed-system transfer device for preparation of antineoplastic agents. J Oncol Pharm Pract, published online 23 August 2013.
2 McMichael DM, Jefferson DM, Carey ET, et al. Utility of the PhaSeal closed system drug transfer device. Am J Pharm Benefits 2011; 3: 9–16.
3 Carey ET, Forrey RA, Haughs D, et al. Second look at utilization of a closed-system transfer device (PhaSeal). Am J Pharm Benefits 2011; 3: 311–318.