Advances in subcutaneous injections: PRECISE II: a study of safety and subject preference for an innovative needle-free injection system

Figures & data

Figure 1. PRIME Device (A), the PRIME Device and Disposable Cartridge (B), and the Injection Process (C).

Table 1. Adverse events.

Subject	1st injection type	Event injection type (location)	Description	Severity	Relationship	Resolution
Subject-018	PRIME	PRIME (abdomen)	Intermittent itchiness left side of abdomen at first PRIME injection site	Mild	Definitely Related	Resolved, no sequelae
Subject-020	PFS	PRIME (abdomen)	Ecchymosis first PRIME injection	Mild	Definitely Related	Resolving at time of lost to follow up^a
Subject-042	PFS	PRIME (abdomen)	Tenderness at first and second PRIME injection sites	Mild	Definitely Related	Resolved, no sequelae
Subject-057	PFS	PFS (thigh)	Ecchymosis at PFS injection site	Mild	Definitely Related	Resolved, no sequelae
Subject-059	PFS	PRIME (abdomen)	Ecchymosis first and second PRIME injection sites	Mild	Definitely Related	Resolved, no sequelae

^aSubject 20 randomized to the abdomen injection location and the PFS for the first injection. He chose the PRIME injection for his third injection method. Subject strongly preferred the PRIME device when answering the preference questions. Images taken of the injection sites at time of study showed minimal erythema. He reported ecchymosis at the first of the PRIME injection sites at the 24–48 hour follow up. He reported resolving ecchymosis over the next 12 days but stopped responding to telephone calls or emails to allow for final resolution.

Figure 2. Distribution of VAS Pain Scores (in mm) at 0 minutes, 5 minutes and 10 minutes for Assigned (A) PRIME Needle-free and (B) Prefilled Needle & Syringe Injections.

Table 2. Average VAS pain scores for PRIME and PFS study injections.

0 Minutes			5 Minutes			10 Minutes
PRIME mean (SD)	PFS mean (SD)	p Value	PRIME mean (SD)	PFS mean (SD)	p Value	PRIME mean (SD)	PFS mean (SD)	p Value
7.8 (8.2)	17.7 (20.0)	.003	2.3 (5.3)	5.1 (9.5)	.032	2.1 (4.8)	3.3 (9.3)	.249

Data are presented as mean (standard deviation), all in millimeters. The mean and standard deviation of 42 subjects’ VAS scores are presented for each injection method at each timepoint. P-value calculated using a paired T-test of two-tailed probability.

Table 3. Additional safety assessments^a.

Local reaction to saline injection	Any observations		Mild (Grade 1)		Moderate (Grade 2)		Severe (Grade 3)		Potentially Life Threatening (Grade 4)
Injection Method:	PRIME	PFS	PRIME	PFS	PRIME	PFS	PRIME	PFS	PRIME	PFS
Tenderness at 5 minutes, events	2/75	3/50	2	3
Tenderness at 10 minutes, events	1/75	0/49	1	0
Other Observations at 5 minutes, events	0/75	2/50	0	2
Other Observations at 10 minutes, events	1/75	1/49	1	1	No observations of any events greater than mild or Grade 1 for either injection method
Erythema/Redness at 5 minutes	23/75	1/50	0	0
Ave diameter (cm), those with event	0.72	1.0	0	0
Erythema/Redness at 10 minutes, events	21/75	0/49	0	0
Ave diameter, (cm) those with event	0.65	0	0	0
Induration/Swelling at 5 minutes	49/75	1/50	0	0
Ave diameter (cm), those with event	0.54	0.30	0	0
Induration/Swelling at 10 minutes, events	35/75	2/49	1/75^b	1/49^c
Ave diameter (cm), those with event	0.42	0.20	4.0	0.2

^aData were available for n = 41 participants, and n = 40 patients for the 10-minute measures.

^bInduration/swelling measures for PRIME injections in one subject were reported as 4.0 cm, however the photos of those injection site did not appear to be that large.

^cInduration/swelling was reported as Grade 1 for the PFS injection at 10 minutes in one subject, however the measured diameter was only reported as 0.2 cm, which does not meet the criteria for Grade 1.

Figure 3. Preference. Response to the question: ‘When comparing the Needle-free Injector to the Prefilled Needle & Syringe, I:’.

Figure 4. Ease of Use. Response to the question: ‘When comparing the Needle-free Injector to the Prefilled Needle & Syringe, it is:’.

Figure 5. Quality of Life. Response to the questions: ‘If you had to inject yourself on a weekly basis because of a chronic illness, which device would you want your physician to prescribe?’.

Figure 6. Medication Adherence. Response to the question: ‘I think the chances that I would take my medication would be:’.