To help others better understand the infusion delivery models today, WeInfuse CEO and Co-Founder Bryan Johnson discusses the various infusion acronyms as distinct categories (e.g. distinct places of service and distinct classes of trade).

Read Part 1 of the two-part blog below.

AIC, AIS, IVC, HOPD, OIC, HIT, SpecRx, and many more. The world of infusion centers, infusion suites, ambulatory infusion suites, pharmacy infusion suites, etc. has continued to grow and become more confusing each year. I think now is a good time to go over many of the various acronyms and models to try to make sense of the pros and cons of the varied offerings. 

Infusion History Lesson

In order to best understand how we got here, it is important that we do a brief flashback to see the evolution of infusion over the past 20 years. I happen to have been around the industry shortly after it started morphing into new delivery models, so I will do my best to recall the changes. 

Infusion started as a hospital-only service. Back in the day, let’s say the mid-1990s and before, the only way for a patient to receive intravenous medication of any kind was in a hospital bed or emergency room. I am sure there were outliers, however, this was the predominant delivery model for intravenous therapy prior to the late 1990s and early 2000s.

Sometime later, home infusion really started taking off as a well-known, alternate delivery solution. This was especially true for patients who were both non-ambulatory and non-acute. At the time, the home infusion model was more often accompanied by a home infusion nurse visit for each treatment. 

In the 1990s and the early 2000s, we started seeing some outpatient infusion popping up, mostly limited to physician offices. This was driven by the need for outpatient chemotherapy (oncology) and HIV/AIDS. Both oncologists and infectious disease specialties had the need to treat their patients in a non-hospital environment that was more convenient for the patient/provider and more cost-effective for everyone. 

Not all oncology patients had an acuity high enough to warrant a hospital bed and the 24-hour care that came with one. Likewise, HIV patients were heavily stigmatized at this time and the hospital not only didn’t want these patients in their facilities, but it was also the last place physicians wanted immunocompromised patients. 

So, there was already a precedent for the idea of an outpatient infusion center and a home infusion delivery model in the late 1990s to early 2000s when the first biologic medications started arriving on the scene (e.g. Remicade). 

At this point in history, we had physician infusion suites, hospital outpatient infusion centers, and home infusion companies. 

You can find more about the history of infusion therapy in our RxToolKit blog, The Past, Present, and Future of IV Therapy.

Infusion Delivery Models – Summary

Ok, now that you are up to date on that brief background of the industry, here is a run-down of the acronyms and the delivery models as I see them today. 

DISCLAIMER: Please understand that I have done my best to categorize these and by no means is this meant to include every kind of combination of services on the market today. I am using the word “infusion” broadly to include antibiotic, antifungal, specialty biologic, IVIG, SQIG, IV iron, hydration, oncology, and pretty much all categories of intravenous therapies. In addition, I tend to include all injectable routes broadly, including IV, IM, Sub-Q, and even some provider-administered specialty inhalation medications.  

Hospital Based Models

Inpatient Hospital 

We have the most obvious of models to get out of the way first. Inpatient Hospital means you are horizontal in a hospital bed in a hospital room for more than 24 hours. I do not often hear any acronyms for this as it’s usually just described as “inpatient” when I hear it. 

Hospital Outpatient Infusion Center (HOPD, HOIC)

This one is also easy to understand. “HOPD” is what I hear most often to describe a Hospital Outpatient Department or Hospital Outpatient Infusion Center. This service is seen most often when patients do not require the acute services of inpatient admission (e.g. oncology) and/or there is not a better ambulatory option in their area. 

HOPD infusion services are also heavily utilized by indigent patients without insurance coverage for services like IV antibiotics, chemotherapy, or other treatments. For claims, most of these services fall under the Outpatient Prospective Payment System (OPPS) for Medicare. OPPS is an entire article in itself and you can read more about OPPS here if interested. 

There are a small number of management companies (MSOs) that offer to fully start and/or manage a HOPD. These are unique situations and have many of the same characteristics as a physician’s office-managed infusion suite (more on that below).

There has been quite a bit of insurance company pushback against the usage of HOPDs in recent years through payor “site of care optimization” strategies in an effort to move patients from higher-cost hospital environments to lower-cost provider-based infusion centers, stand-alone infusion centers, and home infusion (more on those next). 

Hospital Home Infusion Pharmacy/Specialty Pharmacy

I am not aware of a specific acronym delineating between a hospital-owned home infusion pharmacy versus. an independent home infusion pharmacy. Home infusion pharmacies are often referred to as HITs or HIPs (see below)

Hospital-based home infusion and specialty pharmacies have historically operated as more of a need-based service in the community. However, we are seeing this service line more frequently as part of a health system’s strategy to keep more patient revenue (reimbursement) within its own health system, preventing leakage. 

There are now a number of vendors in the space that will consult and even manage a hospital’s home infusion and/or specialty pharmacy (e.g. Cencora, CarePath, Shields, CPS Solutions, etc.). This can include servicing patients on behalf of the hospital-staffed specialty providers in oncology, rheumatology, neurology, etc. 

The big difference in these HIT services is that the hospital/health system owns them. Otherwise, these hospital-based pharmacies operate very similarly to the same non-hospital HIT organizations. That said, many hospital-based home infusion and specialty pharmacies leverage 340B pricing arrangements. In some areas of the country, especially rural areas, the hospital-owned pharmacy is the only provider in the area. 

Physician Office or Provider-Based Models  

Physician/Provider Office-Based (Infusion Suite, OIC)

One of the most prevalent models across the country is an in-office physician infusion center, commonly referred to as an OIC. This is simply a physician’s practice that offers infusion services to their patients. In most cases, these physician practices have a room(s) with a few chairs where they offer their own patients medications that are for diseases they would commonly manage as part of their specialty. For example, a gastroenterology practice may have an infusion suite within its practice administering infusion medications (e.g. Entyvio, Remicade, etc.) for its patients with Crohn’s disease, ulcerative colitis, etc. 

These OICs can vary greatly in size and scope; the very smallest might be a single exam room with a single recliner, and the largest might be an entire floor of their building and/or multiple locations with 10-20 chairs and a dedicated infusion team. Many office-based operations have opened their doors to also treat patients from other providers in the community. This can include provider patients from any specialty. 

The advantages of this model are that the patients are easily found and managed since they are already patients of the practice. Other operational complexities such as supervision requirements, claims, etc. found in other models are typically not an issue since those are kind of baked into the office already. 

Managed Physician/Provider Office-Based (MSO)

This is the same model as above, but some or all of the following services: pre-treatment workflows (benefits investigation); clinical and administrative staffing; inventory procurement and management; and revenue cycle management (billing, claim submission, posting, collections, etc.) are managed by an outside vendor who specializes in the management of infusion suites. These infusion management companies are often called managed service organizations, or MSOs. 

In these MSO arrangements, a practice group that does not want to manage the complexity of operating its own infusion suite(s) can outsource nearly the entire operation. Common MSO organizations include Healix, OI Infusion, Curbside Infusion, and Allied Infusion. 

Of course, the practice’s physicians and providers are still responsible for writing the order for the medications and managing the patient’s underlying disease process, but everything related to the infusion from insurance verification, prior authorizations, inventory, nursing, and revenue cycle can be managed by the MSO. 

Most of these models operate via some kind of management fee model whereby the MSO’s management fee is often based on a percentage of the net profit of the practice’s infusion suite. There are too many variations of this model to go into here, so just know that a management model’s level of service can be limited to a few supporting services or encompass the entire operation. The greater the level of service provided by the MSO, the higher the corresponding management fee.  

Free-Standing Model

Stand-Alone Infusion Center (AIC, IVC)

This model came about in stealth mode in the early-mid 2000s and has grown more rapidly in the past 5-10 years. I know because I co-founded one of these companies (Innovative Infusions) when this idea was very new. 

A stand-alone infusion center will be an office/clinic location dedicated to administering medications, namely intravenous and injection therapy. These AICs do not prescribe/order any of the medications as they don’t diagnose a patient’s underlying disease. Rather, outside physicians/specialists from the community send their patients to these locations for medication administration and treatment.

This is a more competitive model since AICs must win patient referrals from other providers and specialists in their area. AICs tend to market and sell their services more intensely, and also do their best to cater to patients with amenities such as private rooms, beverages, snacks, blankets, and heated recliners to attract referring providers and their patients to their locations. 

AICs are most commonly created as physicians’ office/multi-specialty clinics specializing in the administration of intravenous injection and medication delivery. Due to Medicare and other payer clinical supervision requirements, the AIC model requires the involvement of a physician, nurse practitioner, and/or physician’s assistant. 

There are many regulatory components to this model so I am not going there for this article. The main thing to know is that these AICs are typically set up as provider clinics and bill their claims the same as a physician’s office would (as medical benefit claims under place of service (POS) 11). 

Pharmacy Models

Home Infusion Pharmacy (HIP, HIT)

Easily one of the more established models in this article, a home infusion pharmacy (HIP) is typically a closed-door pharmacy (unlike a retail pharmacy) that services patients who need infusion medications in the home. As mentioned before, this model has been around for a very long time and there are thousands of independent regional home infusion pharmacies across the country, as well as a few with a national footprint. 

An HIP receives its patient orders/prescriptions from hospital case managers, discharge planners, and community physicians and specialists. A HIP can offer a wide variety of therapies, including antibiotics, IVIG, TPN (Total Parenteral Nutrition), enteral, biologic, and a long list of specialty medications. Some home infusion pharmacies may choose to specialize in one or more of these therapies in order to best fit the market need. 

The majority of these home infusion therapy (HIT) medications will be prepared in the pharmacy and dispensed and delivered to a patient’s home via carrier (e.g. UPS, FedEx, etc.) or by courier (e.g. a local delivery driver), as needed. A home infusion nurse either from the HIP itself or an outside nursing agency may also visit the patient’s home to either administer the medication or teach the patient how to administer their own medication.  

An HIP can be a fairly resource-intensive operation if they have a certified cleanroom operation, and more so if they operate in multiple states across the country. HIPs often have wide payor coverage across most commercial health plans, but seem to have limited coverage under Medicare. HIP claims are processed mostly through the medical benefit under POS 12; however, there is a growing trend of HIPs utilizing patients’ pharmacy health plan benefits for claim submission as well (more on that in the “Specialty Pharmacy” section below).

Pharmacy-Based Infusion Suite (AIS)

The pharmacy-based infusion suite is sometimes just referred to as an ambulatory infusion suite (AIS). The naming here has evolved over the years, but the distinction for most still seems to be the use of the word “suite” to describe the pharmacy-based model versus the use of “center” to describe the stand-alone, provider-based model (AIC).

A pharmacy-based infusion suite or AIS is just as it sounds: a room/space inside the physical location of the pharmacy where patients can have their medications administered. The physical setup of the space will most often resemble any physician-based infusion suite or AIC with infusion chairs, IV poles, IV pumps, etc. 

Unlike in a physician-based infusion suite or AIC, a registered nurse is commonly the only clinician (aside from the pharmacist) who is involved in the infusion suite. This is mostly because the pharmacy-based suite is not commonly used to treat Medicare patients and therefore does not have the supervision requirements of the other models. 

An AIS fills a gap for home infusion pharmacies when they have a patient who is either unable or unwilling to administer their own medications to themselves at home, or, in the case that an infusion nurse is needed, that service or that nurse is not available to go to the patient’s home. 

An AIS will send claims the same way that a home infusion pharmacy will, but they have a special set of “S codes” and modifiers to identify the claim as having occurred within a pharmacy infusion suite. 

Specialty Pharmacy (SpecRx)

This newer model in the evolution of our delivery models started gaining popularity in the mid-2000s as more and more biologic medications were FDA-approved that were specifically formulated for patient self-injection/administration. A specialty pharmacy is basically a closed-door pharmacy, without a cleanroom, that manages the delivery of mostly patient-ready, boxed medications. They will also manage and provide other non-injection but high-cost, specialty oral/PO/pill treatments. 

A specialty pharmacy receives their orders/prescriptions the same way as a home infusion pharmacy or stand-alone infusion center would, except they can also receive prescriptions via e-prescribing networks, such as SureScripts. If you walked into a specialty pharmacy, it would look a lot more like a retail pharmacy with more administrative staff. 

Much of the work of a specialty pharmacy is in navigating the medical and/or pharmacy benefit of a patient’s health insurance plan to authorize a patient to receive these high-cost medications. The rest of the work involves patient care coordination, data collection, and, of course, the logistics of delivering the medications to the patient. 

Claims for these medications and services are mostly processed through the pharmacy benefit under the National Council for Prescription Drug Programs’ (NCPDP) network under POS 1 or 12 . There are many hurdles in this model as manufacturers, PBMs, payors, and employer groups have woven a seriously confusing web of pathways through the system. Some specialty medications are under what is called “limited distribution” where only certain pharmacies or pharmacies in the network have access to deliver these medications. There are untold complexities and backchanneling here around rebates to all parties, but we don’t have time to unravel those here in this article. 

Ready for part TWO –Infusion Alphabet Soup Part 2: The Medication Delivery Model? In part two, we talk about organizations combining these various classes of trade and places of service under one parent umbrella with various subsidiaries. Find it here


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