Use of patent term extensions to restore regulatory time for medical devices in the United States

Figures & data

Table 1. Classification of PTE applications by medical specialty.

Time Period Medical Specialty	I (84–93)	II (94–03)	III (04–13)	IV (14–23)	Count	%
Cardiovascular	9	13	16	37	75	42.1%
Orthopedic	2	7	4	10	23	12.9%
Ophthalmic	2	7	3	6	18	10.1%
Gastroenterology & Urology	1	1	1	9	12	6.7%
Neurology		2	3	7	12	6.7%
General & Plastic Surgery	3	4	3	1	11	6.2%
Anesthesiology			4	3	7	3.9%
Obstetrics/Gynecology	1	3		1	5	2.8%
Radiology	1	2		1	4	2.2%
Hematology				3	3	1.7%
Clinical Chemistry			1	1	2	1.1%
Pathology			1	1	2	1.1%
General Hospital	1				1	0.6%
Dental			1		1	0.6%
Ear, Nose, & Throat				1	1	0.6%
Physical Medicine				1	1	0.6%
Immunology					0	0.0%
Microbiology					0	0.0%
Clinical Toxicology					0	0.0%
Total	20	39	37	82	178	100%

Table 2. Average PTE durations for different product types.

Product Type*	Mean ± S.D.^†	N	%	N of FDA Approvals
BLA	1057.0 ± 523.4	140	14.1%	746^‡
Food Additive	1132.0 ± 487.5	11	1.1%
NADA	1101.5 ± 468.5	49	4.9%
NDA	1063.4 ± 518.3	670	67.3%	1040^‡
PMA	987.2 ± 560.7	125	12.6%	1251^§
Total	1055.6 ± 521.6	995	100.0%

*Abbreviations for different product types. BLA: Biologics License Application; NADA: New Animal Drug Application; NDA: New Drug Application; PMA: Premarket Approval.

^†S.D. = Standard Deviation.

^‡CDER NME and New Biologic Approvals 1985–2023 and Biologic Approvals in the Purple Book 2023 December Editon.

^§The number of PMAs whose decision date is between January 1, 1984, through December 31, 2023.

^¶ANOVA analysis conducted on the granted period of extension (in days) revealed no statistically significant differences among various product types with respect to the time restored (Levene’s Test of Equality of Error Variances between means: 1.774, Sig. 0.132, p ≤ 0.05).

Table 3. Changes in rates of PTEs over time.

PMA Decision Year in 4 Periods	Group	Total Number of PTEs in 4 Groups				Count
		A (8)*	B (3–4)	C (2)	D (1)**
I (84–93)	Count	4	2	2	12	20
	% within PMA Decision Year	20.0%	10.0%	10.0%	60.0%	100.0%
	% within PTE Group	16.7%	5.3%	7.1%	13.6%	11.2%
	% of Total	2.2%	1.1%	1.1%	6.7%	11.2%
II (94–03)	Count	4	16	2	17	39
	% within PMA Decision Year	10.3%	41.0%	5.1%	43.6%	100.0%
	% within PTE Group	16.7%	42.1%	7.1%	19.3%	21.9%
	% of Total	2.2%	9.0%	1.1%	9.6%	21.9%
III (04–13)	Count	8	7	6	16	37
	% within PMA Decision Year	21.6%	18.9%	16.2%	43.2%	100.0%
	% within PTE Group	33.3%	18.4%	21.4%	18.2%	20.8%
	% of Total	4.5%	3.9%	3.4%	9.0%	20.8%
IV (14–23)	Count	8	13	18	43	82
	% within PMA Decision Year	9.8%	15.9%	22.0%	52.4%	100.0%
	% within PTE Group	33.3%	34.2%	64.3%	48.9%	46.1%
	% of Total	4.5%	7.3%	10.1%	24.2%	46.1%
	Total	24	38	28	88	178
	% within PMA Decision Year	13.5%	21.3%	15.7%	49.4%	100.0%
	% within PTE Group	100.0%	100.0%	100.0%	100.0%	100.0%
	% of Total	13.5%	21.3%	15.7%	49.4%	100.0%

Individual PTE applications increased significantly in recent time periods. Group A: Products with a total of 8 PTE applications with the same product code; Group B: Products with a total of 3 to 5 PTE applications with the same product code; Group C: Products with a total of 2 PTE applications with the same product code; Group D: Products with only 1 PTE application associated with the product code.

Table 4. Chi-square tests.

	Value	df	Asymptotic Significance (2-sided)	Exact Sig. (2-sided)
Likelihood Ratio	19.003	9	0.025	0.036
Fisher-Freeman-Halton Exact Test	17.989			0.028
N of Valid Cases	178

Table 5. Competitiveness analysis identified four primary types of product codes based on PTE filing conditions.

Medical Specialty	Fierce Competition	Strong Competition	No Competition	Sole Company	Count
Cardiovascular	5	7	11	15	38
Ophthalmic	1	2	9	1	13
General & Plastic Surgery	1	1	2	1	5
Orthopedic		4	4	8	16
Gastroenterology/Urology		1	4	6	11
Obstetrics/Gynecology		1	3		4
Neurology		1	1	6	8
Anesthesiology			2	5	7
Radiology			2	2	4
Clinical Chemistry			1	1	2
Dental			1		1
Ear, Nose & Throat			1		1
General Hospital			1		1
Pathology				2	2
Hematology				2	2
Physical Medicine				1	1
Total	7	17	42	50	116
%	6.0%	14.7%	36.2%	43.1%	100.0%

Table 6. Examples of product codes categorized into one of the four competition categories.

Medical Specialty	Medical Specialty	Product Code	I (84–93)	II (94–03)	III (04–13)	IV (14–23)	PTE Count	PMA Count	% PMA Seeking for PTE	PMA & Supplements Count	PTE Company Count	PTE/PTE Company	PMA Company Count	Competition Level
Cardiovascular	CV	LWS	4	3	1		8	27	30%	2539	4	2.0	7	Fierce Competition
Cardiovascular	CV	NIQ		1	6	1	8	16	50%	1307	4	2.0	8	Fierce Competition
Cardiovascular	CV	NPT			1	7	8	7	114%	574	3	2.7	4	Fierce Competition
Cardiovascular	CV	LWQ	1	2			3	12	25%	367	3	1.0	8	Strong Competition
General & Plastic Surgery	SU	LMH	1	1	2	1	5	17	29%	882	4	1.3	10	Fierce Competition
Cardiovascular	CV	MAF		4			4	24	17%	860	3	1.3	10	Fierce Competition
General & Plastic Surgery	SU	MGR		3			3	5	60%	162	3	1.0	4	Strong Competition
Orthopedic	OR	MAX		3			3	6	50%	58	3	1.0	6	Strong Competition
Ophthalmic	OP	HQL		2		1	3	67	4%	1577	2	1.5	23	Fierce Competition
Neurology	NE	LGW		1		2	3	8	38%	1165	3	1.0	8	Strong Competition
Cardiovascular	CV	MIH			3	1	4	21	19%	935	4	1.0	9	Strong Competition
Orthopedic	OR	MJO			2	2	4	13	31%	197	4	1.0	9	Strong Competition
Cardiovascular	CV	LWR				3	3	13	23%	506	2	1.5	5	Fierce Competition
Neurology	NE	NHL				3	3	2	150%	62	1	3.0	2	No Competition
Cardiovascular	CV	DXY	2				2	20	10%	632	2	1.0	8	Strong Competition
Obstetrics/Gynecology	OB	MNB		1		1	2	9	22%	269	2	1.0	7	Strong Competition
Orthopedic	OR	MOZ		1		1	2	14	14%	287	2	1.0	9	Strong Competition
Orthopedic	OR	NQO			2		2	3	67%	65	2	1.0	3	Strong Competition
Gastroenterology/Urology	GU	LNM			1	1	2	9	22%	257	2	1.0	8	Strong Competition
Ophthalmic	OP	OGO			1	1	2	5	40%	68	1	2.0	3	No Competition
Cardiovascular	CV	OAE			1	1	2	10	20%	289	2	1.0	6	Strong Competition
Cardiovascular	CV	NKM			1	1	2	2	100%	74	2	1.0	2	Strong Competition
Cardiovascular	CV	NIP				2	2	12	17%	487	2	1.0	9	Strong Competition
Ophthalmic	OP	LQE				2	2	3	67%	27	2	1.0	3	Strong Competition
Hematology	HE	PJF				2	2	2	100%	73	1	2.0	1	Sole Company
Cardiovascular	CV	PNJ				2	2	2	100%	184	2	1.0	2	Strong Competition
Ophthalmic	OP	POE				2	2	4	50%	13	2	1.0	3	Strong Competition
Cardiovascular	CV	QCT				2	2	2	100%	14	1	2.0	1	Sole Company
Gastroenterology/Urology	GU	LNR	1				1	1	100%	105	1	1.0	1	Sole Company
General & Plastic Surgery	SU	GAS	1				1	6	17%	50	1	1.0	4	No Competition
General & Plastic Surgery	SU	GAM	1				1	3	33%	29	1	1.0	2	No Competition