Exam 3 Biologics: Prefilled Syringes, Pens, and Autoinjectors

Question 1

What is the indication and dosage form for Humira (a MAb)?

Answer 1

indication: rheumatoid arthritis

dosage form: pen, pre-filled syringe

Question 2

What is the indication and dosage form for Lantus?

Answer 2

indication: diabetes (long acting insulin)

dosage form: pre-filled pen

Question 3

What is the indication and dosage form for Aranesp?

Answer 3

indication: anemia of renal failure

dosage form: pre-filled syringe, pen

Question 4

What is the indication and dosage form of Rebif?

Answer 4

indication: MS

dosage form: pre-filled syringe, auto-injector

Question 5

What is one of the reasons why biologics have been so successful?

Answer 5

because of the availability of these devices and the way that they enable the patients to self administer these drugs

Question 6

What are some important things to remember about pre-filled syringes, pens, and autoinjectors?

Answer 6

1. technically, prefilled syringes, pens, and autoinjectors are NOT formulations (aka NOT dosage forms)
2. the pen (or syringe or autoinjector) is a medical device
3. the solution inside the pen (or syringe or autoinjector) is the formulation
4. together, they are called a combination produce → combo of a formulation and a medical device

Question 7

What are advantages of pre-filled syringes, pens, and autoinjectors?

Answer 7

1. ease of use, convenience
2. easier to transport than vial and syringe → easier for patient to carry it with them
3. discrete
4. increased patient compliance + adherence
5. reduced risk of dosage error → devices are designed to make sure correct dose is administered
6. reduced risk of product contamination → not opening/closing vial multiple times

Question 8

What are disadvantages of pre-filled syringes, pens, and autoinjectors?

Answer 8

1. higher cost than vial plus syringe
2. cannot mix two drugs (example is insulin types) → can’t mix rapid and long acting insulins in addition to it being difficult to co-administer two insulins in one device
3. drug waste due to priming
4. greater surface to volume ratio, presence of lubricants (so syringe barrel moves smoothly), can induce aggregation of protein drugs

Question 9

What are the components of a pre-filled syringe?

Answer 9

1. syringe barrel → place where the drug is
2. luer lock → links drug to the needle or links the barrel to the needle
3. finger grip → allows the plunger to be pushed forward
4. plunger
5. gasket → seals everything so nothing leaks between the plunger and barrel
6. top cap → helps cover the syringe needle

Question 10

What are the components of an insulin pen?

Answer 10

1. pen cap
2. outer needle cap
3. inner needle cap
4. needle
5. protective seal
6. rubber seal
7. insulin reservoir
8. dose window
9. dosage knob
10. injection button

Question 11

Insulin pens are often designed for what?

Answer 11

they are often designed for multiple use but the syringe itself is single use

Question 12

Pre-filled syringes, pens, and autoinjectors are typically what?

Answer 12

they are usually solution dosage forms within a device for administration of the formulation and are typically administered IV, IM, or SC

Question 13

What are common features of pre-filled syringes, autoinjectors, and pens?

Answer 13

1. drug solution
2. needle
3. piston or plunger → activating the device
4. housing → contains everything

Question 14

When compared to vials containing solutions for injection, these devices (pens, pre-filled syringes, autoinjectors) have:

Answer 14

1. higher surface to volume ratio
2. lower total volume
3. syringe lubricants, oils → change interaction or proteins with solid surface, droplets in solution

Question 15

Proteins are what?

Answer 15

surfactants and can unfold when exposed to surfaces or interfaces → particularly interfaces or hydrophobic surfaces

Question 16

Why is there a greater risk for aggregation with pre-filled syringes, pens, and autoinjectors?

Answer 16

1. hydrophobic syringe lubricants coat the inside of the barrel surface
2. unfolded protein can stick to the surface of the oil droplet since lubricant on wall of syringe barrel is hydrophobic and coat the inside of the barrel since it is more hydrophobic than the surface
3. suspended oil droplets provide additional hydrophobic surface area in addition to the surface of the syringe and the partially unfolded protein can then go back into solution and form a dimer and then aggregate → greater risk for aggregation!

Question 17

What is an overall summary for pens, autoinjectors, and pre-filled syringes?

Answer 17

1. pre-filled syringes, pens, and autoinjectors are used (usually) to deliver solution formulations of biologics → freeze dried biologics are an exception
2. formulation concerns for biologics in solution apply → even though it is a solution formulation within a medical device
3. higher surface to volume ratio than in vials, and the use of lubricants (to allow barrels to move smoothly) may promote aggregation (more so than solutions in vials)