Cost per additional responder for ixekizumab and other FDA-approved biologics in moderate-to-severe plaque psoriasis

Abstract

Background: Evidence of the cost-efficacy of ixekizumab for the treatment of moderate-to-severe plaque psoriasis (PsO) in the US is limited.

Objective: To estimate the number needed to treat (NNT) and monthly cost of achieving one additional Psoriasis Area and Severity Index (PASI) 75, 90, and 100 responder for ixekizumab and other Food and Drug Administration (FDA)-approved biologics in PsO.

Methods: A network meta-analysis estimated the probability of achieving PASI 75, 90, or 100 response during induction for each biologic. NNTs were calculated using response difference of each respective biologic vs placebo at the end of induction. Monthly costs per additional PASI responder were based on FDA-approved doses, wholesale acquisition costs, and induction NNTs.

Results: Induction NNTs for ixekizumab 80 mg once every 2 weeks (Q2W) relative to placebo were consistently lower across all levels of clearance compared with the other biologics. Monthly cost per additional responder was lowest for ustekinumab 45 mg at PASI 75 and for secukinumab 300 mg and ixekizumab 80 mg Q2W at PASI 90. Ixekizumab 80 mg Q2W had the lowest cost for PASI 100.

Conclusion: In this analysis, ixekizumab is the most cost-efficient biologic in the US when targeting complete resolution, as measured by PASI 100 in PsO.

Keywords:

• Moderate-to-severe plaque psoriasis
• ixekizumab
• FDA-approved biologics
• network meta-analysis
• number needed to treat
• cost per additional responder
• Psoriasis Area Severity Index (PASI)

Background

Psoriasis is a chronic inflammatory disorder that affects 2–3% of the adult US population^1–3. Plaque psoriasis (PsO), which constitutes 79–90% of patients with psoriasis, is characterized by red, scaly skin plaques that are typically present on the scalp, knees, elbows, and/or lower back, and are often accompanied by bothersome symptoms such as itching and pain^1,3,4. Approximately 20% of patients with PsO have moderate-to-severe disease, defined by the American Association of Dermatology as ≥5% body surface area (BSA) involvement or involvement of certain body areas such as the hands, feet, face, or genitals, which have a significant impact on patients’ health-related quality-of-life (HRQoL)¹.

Approved biologic agents for moderate-to-severe PsO have significantly shifted the treatment paradigm by presenting patients and healthcare providers with treatment options that have improved benefit-risk profiles compared to traditional systemic therapies⁵. Such biologics have allowed a high proportion of patients with PsO to achieve desired levels of skin clearance (i.e. almost clear to clear skin) that are associated with significant improvements in HRQoL^6,7. In the US, several biologics have been approved for the treatment of moderate-to-severe PsO, including tumor necrosis factor (TNF)-alpha blockers (adalimumab, etanercept, and infliximab)^8–10, an interleukin (IL)-12/23 inhibitor (ustekinumab)¹¹, and an IL-17A inhibitor (secukinumab)¹². In 2016, the US Food and Drug Administration (FDA) approved ixekizumab, a novel IL-17A inhibitor, for the treatment of patients with moderate-to-severe PsO¹³. Ixekizumab has demonstrated superior efficacy, as measured by Psoriasis Area and Severity Index (PASI), compared with placebo, etanercept, and ustekinumab, in a controlled clinical trial setting (UNCOVER-1 [NCT01474512], UNCOVER-2 [NCT01597245], UNCOVER-3 [NCT01646177], and IXORA-S [NCT02561806])^14–16.

Despite the strength of the direct evidence demonstrating the higher efficacy of ixekizumab as compared with both etanercept and ustekinumab in the UNCOVER and IXORA-S trials, respectively, evidence of the clinical efficacy of ixekizumab compared with other FDA-approved biologics indicated for the treatment of moderate-to-severe PsO remains limited. To address this gap, several published analyses have estimated the efficacy of ixekizumab relative to other biologics using robust statistical methods of adjusted indirect comparison or network meta-analysis (NMA), or have simply compared clinical efficacies across clinical trials using standardized estimates such as number needed to treat (NNT)^17–19. However, these methodologies have associated limitations that may be, at least partially, overcome by combining strategies to estimate NNTs using the relative efficacy findings of robust indirect comparisons or NMAs. This would not only provide more reliable NNT estimates to compare clinical efficacies across clinical trials, but may also help translate the complex findings of these methodologies to everyday clinical practice.

The NNT is an evidence-based tool often used in immunology to provide information on the relative benefit of systemic therapies within or across different indications^20–23. The NNT refers to the number of individuals that need to be treated by a given therapy to achieve the desired outcome in a single individual relative to a reference group such as placebo. The closer the value of the NNT is to 1, the more favorable the outcome. NNT values have also been used to calculate incremental costs, making it a useful measure for economic decision-making.

For the purpose of this analysis, an NMA was undertaken to evaluate the efficacy, relative to placebo, of ixekizumab 80 mg once every 2 weeks (Q2W, i.e. the FDA-approved induction dosing regimen of ixekizumab in PsO²⁴) compared with those of other FDA-approved biologics indicated for the treatment of moderate-to-severe PsO. This US-centric NMA was a sub-analysis of a more comprehensive NMA reported elsewhere¹⁸. The relative efficacy findings generated from this NMA were used to estimate the NNT to achieve one additional PASI responder for ixekizumab and other FDA-approved biologics across different levels of clearance (PASI 75, 90, and 100) at the end of each respective biologic induction period. Using these NNT values, the cost of achieving one additional PASI 75, 90, or 100 responder was then calculated for each of the corresponding biologics.

Methods

Detailed methodology pertaining to the original comprehensive NMA and its associated systematic literature review (SLR) has been presented elsewhere¹⁸. This NMA was a sub-analysis of the comprehensive NMA and, therefore, the same SLR criteria applied, except for the evaluated comparators, which were restricted to FDA-approved biologics prior to 2017^8,9,11,12,24, indicated for the treatment of moderate-to-severe PsO at their respective approved US prescribing information (PI) doses (Table 1)²⁵. Brodalumab was not included in the analyses as it was not FDA-approved at the time of completion of this NMA. Infliximab was also excluded given its different mode of administration (infusion) from the evaluated biologics included in this analysis, and its subsequent reimbursement under medical benefit¹⁰.

Table 1. US PI dosing schedule, length of induction period based on the respective biologic clinical trials design, US WAC per dose, and calculated cost per induction period per patient.

Treatment	FDA-approved US PI dosing schedule	Duration of induction period per biologic	Total number of doses during induction period per US PI	WAC per dose^26	Calculated cost per induction period per patient
Adalimumab	80 mg (week 0), 40 mg EOW starting at week 1^7	16 weeks	10 × 40 mg dose	$2,220.62	$22,206
Etanercept	50 mg BIW for 3 months, 50 mg weekly thereafter^8	12 weeks	24 × 50 mg dose	$1,110.50	$26,652
Ixekizumab	160 mg (week 0), 80 mg (weeks 2, 4, 6, 8, 10, and 12), 80 mg Q4W thereafter^23	12 weeks	7 × 80 mg dose	$4,469.00	$31,283
Secukinumab	300 mg (weeks 0, 1, 2, 3, and 4), 300 mg Q4W thereafter^11	12 weeks	12 × 150 mg dose	$2,154.22	$25,851
Ustekinumab (for patients weighing ≤100 kg)	45 mg (weeks 0, 4, and every 12 weeks thereafter)^10	12 weeks	2 × 45 mg dose	$9,538.60	$19,077
Ustekinumab (for patients weighing >100 kg)	90 mg (weeks 0, 4, and every 12 weeks thereafter)^10	12 weeks	2 × 90 mg dose	$19,077.20	$38,154

All costs presented as US dollars as of March 14, 2017.

BIW, twice weekly; EOW, every other week; FDA, Food and Drug Administration; PI, prescribing information; Q4W, every 4 weeks; US, United States; WAC, wholesale acquisition cost.

In brief, input data for the comprehensive NMA were identified through an SLR of published and grey literature, following guidelines from the Cochrane Handbook of Systematic Reviews and Interventions²⁶. This review covered publications in English language from January 1990 to November 2015 and included phase II, III, and IV randomized-controlled trials (RCTs) of relevant conventional systemic and biologic therapies in moderate-to-severe PsO¹⁸. Baseline criteria (RCT design, patient characteristics, disease severity, etc.) of the studies included in the NMA were assessed for comparability. Cochran’s Q test was used to test for heterogeneity in the RCTs included in the evidence network. Consistency within the network was evaluated using a net heat map²⁷.

The NMA used a random effects Bayesian model for multi-arm trials with a multinomial likelihood and probit link developed for simultaneous PASI response analyses comparing all possible comparators. All analyses were executed according to international guidelines for the conduct of NMAs and included standard consistency and heterogeneity tests^26,28. The end of induction period PASI 75, 90, and 100 were the main outcomes of the NMA, defined as ≥75% improvement of PASI score from baseline, ≥90% improvement of PASI score from baseline, and complete resolution of skin plaque, respectively. Missing data were imputed using non-responder imputation.

For this analysis, the NNT to achieve an additional PASI 75, 90, or 100 responder was calculated for ixekizumab, and each of the other FDA-approved biologics using the response difference of each respective biologic vs placebo at the end of induction: NNT =1/(probability of response with biologic – probability of response with placebo). NNT point estimates and 95% credible intervals (Cr.Is) were based on PASI 75, 90, and 100 response rates at the end of week 12 for all evaluated biologics except adalimumab (week 16). The duration of induction was based on the length of induction phase, as described for each respective biologic in their clinical trials design.

Cost calculations

Induction period biologic cost calculations were based on the total number of doses administered during induction defined as a total of 12 weeks (except for adalimumab, which was 16 weeks). The total number of doses during induction was according to the FDA-approved US PI dosing schedule for the evaluated biologics (Table 1). Biologic costs were calculated with the assumption of 100% adherence to the indicated doses during the timeframe evaluated and were based on US wholesale acquisition costs (WAC, the list price of a drug product to wholesalers without inclusion of discounts, rebates, reductions, or other factors affecting price) per dose in US dollars ($US), as of March 14, 2017, derived from the Truven Health Analytics RED BOOK (Table 1)²⁵. Administration costs were not included in the analysis.

For comparison across the different biologics, cost calculations were standardized by calculating the monthly (i.e. 30-day) cost per additional PASI 75, 90, or 100 responder during the induction period for each biologic, which would be a helpful comparative metric for economic decision-making.

Results

In total, 24 studies were included in this NMA (Table 2). The estimated probability of achieving a PASI 75, 90, or 100 response (and corresponding response difference) was consistently highest with ixekizumab 80 mg Q2W vs placebo compared with the other biologics included in the NMA (Table 3). Similarly, the observed NNTs for ixekizumab 80 mg Q2W relative to placebo were consistently lower across all levels of clearance (PASI 75, 90, and 100) compared with all other biologics included in the NMA (Table 4, Figure 1). Etanercept 50 mg twice weekly (BIW) had the highest NNT across all levels of clearance.

Figure 1. Number needed to treat per additional PASI 75, 90, or 100 responder vs placebo for each of the evaluated biologics (non-responder imputation). Error bars represent 95% Cr.I. BIW, twice weekly; Cr.I, credible interval; EOW, every other week; PASI, Psoriasis Area and Severity Index; Q2W, every 2 weeks.

Table 2. Summary of studies included in FDA-approved US PI dose NMA.

Treatment	Study name	Reference	No. of patients	Treatment duration (weeks)	PASI outcomes reported
Adalimumab 80 mg/40 mg EOW	CHAMPION	Saurat et al.^29	108	16	75, 90, 100
	REVEAL	Menter et al.^30	814	16	75, 90, 100
	Asahina	Asahina et al.^31	43	16	75, 90
	Bissonnette	Bissonnette et al.^32	20	16	75
	Gordon	Gordon et al.^33	43	16	75, 90, 100
Etanercept 50 mg BIW	ACCEPT	Griffiths et al.^34	347	12	75, 90
	FIXTURE	EMA^35	323	12	75, 90, 100
	UNCOVER-2	Griffiths et al.^14	358	12	75, 90, 100
	UNCOVER-3	Griffiths et al.^14	382	12	75, 90, 100
	Leonardi	Leonardi et al.^36	164	12	75, 90
	Papp	Papp et al.^37	194	12	75, 90
	NCT00111449	Tyring et al.^38	311	12	75, 90
	Bachelez	Bachelez et al.^39	335	12	75, 90
	Bagel	Bagel et al.^40	62	12	75, 90
Ixekizumab 80 mg Q2W	UNCOVER-1	Gordon et al.^15	433	12	75, 90, 100
	UNCOVER-2	Griffiths et al.^14	351	12	75, 90, 100
	UNCOVER-3	Griffiths et al.^14	385	12	75, 90, 100
Secukinumab 300 mg	ERASURE	EMA^35	245	12	75, 90, 100
	FEATURE	EMA^35	58	12	75, 90, 100
	FIXTURE	EMA^35	323	12	75, 90, 100
	JUNCTURE	EMA^35	60	12	75, 90, 100
	CLEAR	Thaçi et al.^7	334	12	75, 90, 100
Ustekinumab 45 mg	ACCEPT	Griffiths et al.^34	209	12	75, 90
	LOTUS	Zhu et al.^41	160	12	75, 90, 100
	PEARL	Tsai et al.^42	61	12	75, 90, 100
	PHOENIX 1	Leonardi et al.^43	255	12	75, 90, 100
	PHOENIX 2	Papp et al.^44	409	12	75, 90, 100
	Igarashi	Igarashi et al.^45	64	12	75, 90
Ustekinumab 90 mg	ACCEPT	Griffiths et al.^34	347	12	75, 90
	PHOENIX 1	Leonardi et al.^43	256	12	75, 90, 100
	PHOENIX 2	Papp et al.^44	411	12	75, 90, 100
	Igarashi	Igarashi et al.^45	62	12	75, 90

BIW, twice weekly; EOW, every other week; FDA, Food and Drug Administration; NCT, ClinicalTrials.gov registry number; PASI, Psoriasis Area and Severity Index; PI, prescribing information; Q2W, every 2 weeks; US, United States.

Table 3. Conditional probabilities of achieving ≥75%, ≥ 90%, or 100% PASI response and response differences vs placebo for each of the evaluated biologics.

Treatment	Probability of ≥ PASI 75 response			Probability of ≥ PASI 90 response			Probability of PASI 100 response
	Treatment (%)	Placebo (%)	Response difference vs placebo (Cr.I)	Treatment (%)	Placebo (%)	Response difference vs placebo (Cr.I)	Treatment (%)	Placebo (%)	Response difference vs placebo (Cr.I)
Adalimumab 80 mg/40 mg EOW	57.0	4.4	0.53 (0.42–0.63)	30.7	0.8	0.30 (0.20–0.41)	9.2	0.1	0.09 (0.05–0.15)
Etanercept 50 mg BIW	50.4	4.4	0.46 (0.39–0.53)	25.0	0.8	0.24 (0.18–0.31)	6.7	0.1	0.07 (0.04–0.10)
Ixekizumab 80 mg Q2W	89.7	4.4	0.85 (0.81–0.89)	72.0	0.8	0.71 (0.62–0.79)	40.5	0.1	0.40 (0.30–0.51)
Secukinumab 300 mg	82.8	4.4	0.78 (0.72–0.84)	60.3	0.8	0.60 (0.50–0.69)	28.7	0.1	0.29 (0.20–0.38)
Ustekinumab 45 mg	69.0	4.4	0.65 (0.56–0.72)	42.6	0.8	0.42 (0.32–0.51)	15.6	0.1	0.16 (0.10–0.22)
Ustekinumab 90 mg	73.0	4.4	0.69 (0.60–0.76)	47.2	0.8	0.46 (0.36–0.57)	18.6	0.1	0.18 (0.12–0.26)

Posterior mean probability (95% credible interval).

BIW, twice weekly; Cr.I, credible interval; EOW, every other week; PASI, Psoriasis Area and Severity Index; Q2W, every 2 weeks.

Table 4. Number needed to treat per additional PASI 75, 90, or 100 responder vs placebo for each of the evaluated biologics.

Treatment	PASI 75		PASI 90		PASI 100
	NNT	Cr.I	NNT	Cr.I	NNT	Cr.I
Adalimumab 80 mg/40 mg EOW	1.9	1.6–2.4	3.5	2.5–4.9	11.8	6.8–20.3
Etanercept 50 mg BIW	2.2	1.9–2.6	4.2	3.2–5.6	15.9	10.2–24.1
Ixekizumab 80 mg Q2W	1.2	1.1–1.2	1.4	1.3–1.6	2.5	2.0–3.3
Secukinumab 300 mg	1.3	1.2–1.4	1.7	1.4–2.0	3.6	2.6–4.9
Ustekinumab 45 mg	1.6	1.4–1.8	2.4	2.0–3.1	6.7	4.6–10.0
Ustekinumab 90 mg	1.5	1.3–1.7	2.2	1.8–2.8	5.6	3.8–8.5

Posterior mean NNT (95% credible interval).

BIW, twice weekly; Cr.I, credible interval; EOW, every other week; NNT, number needed to treat; PASI, Psoriasis Area and Severity Index; Q2W, every 2 weeks.

The monthly cost per additional PASI 75, 90, or 100 responder per biologic is shown in Table 5 and Figure 2. The monthly cost per additional PASI 75 responder was lowest for ustekinumab 45 mg, followed by adalimumab 40 mg, secukinumab 300 mg, and ixekizumab 80 mg Q2W, while it was higher for ustekinumab 90 mg and etanercept 50 mg BIW. For PASI 90, secukinumab 300 mg and ixekizumab 80 mg Q2W had the lowest monthly costs per additional responder followed by ustekinumab 45 mg, adalimumab 40 mg, ustekinumab 90 mg, and etanercept 50 mg BIW. Ixekizumab 80 mg Q2W had the lowest monthly cost per additional PASI 100 responder. Ustekinumab 90 mg and etanercept 50 mg BIW had the highest monthly cost per additional responder for PASI 100 as for all other evaluated levels of clearance.

Figure 2. Cost per additional PASI 75, 90, or 100 responder per month (30 days) for each of the evaluated biologics. All costs presented as US dollars. Error bars represent 95% Cr.I. BIW, twice weekly; Cr.I, credible interval; EOW, every other week; PASI, Psoriasis Area and Severity Index; Q2W, every 2 weeks.

Table 5. Cost (US$) per additional PASI 75, 90, or 100 responder standardized per month (30 days) for each of the evaluated biologics.

Treatment	PASI 75		PASI 90		PASI 100
	Cost	Cr.I	Cost	Cr.I	Cost	Cr.I
Adalimumab 80 mg/40 mg EOW	$11,420	9,398–14,216	$20,521	14,632–29,265	$70,128	40,566–120,567
Etanercept 50 mg BIW	$20,846	17,800–24,653	$40,168	30,745–53,018	$151,440	97,185–229,017
Ixekizumab 80 mg Q2W	$13,072	12,625–13,854	$15,753	14,077–18,099	$28,155	21,898–36,869
Secukinumab 300 mg	$11,817	11,079–12,833	$15,603	13,295–18,557	$33,052	24,189–45,423
Ustekinumab 45 mg	$10,561	9,470–12,060	$16,556	13,286–21,053	$45,717	31,000–68,065
Ustekinumab 90 mg	$19,895	17,987–22,756	$29,842	24,119–38,018	$76,718	52,326–115,281

All costs presented as US dollars.

BIW, twice weekly; Cr.I, credible interval; EOW, every other week; PASI, Psoriasis Area and Severity Index; Q2W, every 2 weeks.

Discussion

Advances in the management of PsO, including the development and approval of biologics, have brought with them the need for robust comparative analytics and creative evidence-based tools to facilitate the translation of comparative evidence for healthcare decision-makers. This study presents findings from an NMA evaluating the relative clinical efficacy and associated costs of biologics indicated for the treatment of moderate-to-severe PsO in the US. NMA is a particularly useful statistical approach when direct head-to-head pairwise comparisons are not available in the literature, as it combines direct and indirect evidence to provide a global estimate of treatment effects for a set of therapies^46,47. The findings of this NMA consistently demonstrated the higher efficacy, relative to placebo, of ixekizumab 80 mg Q2W as compared with secukinumab 300 mg, ustekinumab (90 mg, 45 mg), adalimumab 40 mg, and etanercept 50 mg BIW (in decreasing order of efficacy) across all levels of clearance (PASI 75, 90, or 100). These findings are consistent with those reported by Reich et al.⁴⁸. Although Reich et al.’s analysis included a different range of treatment options and PASI end-points, ustekinumab (90 mg, 45 mg), adalimumab, and etanercept were ranked in the same order in terms of predicted mean probability of response at PASI 50, 75, and 90.

Similarly, the lower NNT value for ixekizumab, calculated based on estimated response differences between ixekizumab vs placebo, showed a superior efficacy for ixekizumab to any of the other evaluated biologics at the different levels of clearance (PASI 75, PASI 90, PASI 100). The NNT results of this study are consistent with those reported by Poulin et al.⁴⁹, who estimated an average PASI 75 NNT of 1.5 for ustekinumab 90 mg, 1.6 for adalimumab and ustekinumab 45 mg, and 2.3 for etanercept, based on individual clinical studies, compared with our estimates of 1.5 for ustekinumab 90 mg, 1.9 for adalimumab 40 mg, 1.6 for ustekinumab 45 mg, and 2.2 for etanercept.

The results of the current study showed that, after translating the NNTs into cost per NNT based on the US WAC, the observed range of the monthly cost per additional responder among the evaluated biologics is relatively narrow for the PASI 75 response ($US10,561–$20,846), but the range widens at the higher levels of clearance, with the widest range in costs for achieving PASI 100 ($US28,155–$US151,440). For example, at the PASI 75 level, the monthly cost per additional responder ranged from $US10,561 for ustekinumab 45 mg to $US13,072 for ixekizumab 80 mg Q2W and $US20,846 for etanercept 50 mg BIW. For PASI 90, secukinumab 300 mg and ixekizumab 80 mg Q2W had the lower monthly costs per additional responder estimated at $US15,603 and $US15,753, respectively, while etanercept 50 mg BIW had the highest cost ($US40,168). As for the PASI 100 level, the monthly cost per additional responder was lowest for ixekizumab ($US28,155) and highest for etanercept 50 mg BIW ($US151,440). The results from this study suggest that, as management goals in the treatment of moderate-to-severe PsO evolve to target the highest possible levels of clearance, there is a clear separation in costs per NNT that favors the biologics with improved efficacy at the PASI 90 or 100 levels, such as the case with ixekizumab. This study showed that ixekizumab provided significantly lower monthly costs per additional PASI 100 responder compared with all other evaluated biologics (i.e. $US28,155 for ixekizumab compared to $US33,052 for secukinumab, $US45,717 for ustekinumab 45 mg, $US70,128 for adalimumab, $US76,718 for ustekinumab 90 mg, and $US151,440 for etanercept). There is increasing evidence demonstrating that patients who achieve complete skin clearance reported no psoriasis symptoms and no impairment in HRQoL within an acceptable safety profile^5,50,51.

The monthly costs per responder results from this study are comparable with a previously reported cost-efficacy analysis of US FDA-approved systemic treatments for moderate-to-severe PsO by D’Souza and Payette²², which estimated monthly costs per NNT to achieve PASI 75 as $US3,974.61–$US7,678.78 for adalimumab, $US7,177.89–$US7,263.99 for ustekinumab 45 mg, and $US8,284.71–$US10,674.89 for etanercept. Even though biologics prices had increased from the time their analyses were conducted, the rank of cost per NNT stayed the same for the evaluated biologics in both studies.

Strengths and limitations

The NMA on which the current NNT data are based has been developed in line with current health technology assessment methods guidance and has provided robust results, which have been confirmed in a wide range of sensitivity analyses¹⁸. One limitation is that the heterogeneity of RCT designs across the included comparators beyond the induction period did not allow assessment of the relative efficacy of ixekizumab over longer time periods.

This analysis was based on efficacy results from clinical trials and not on real-world data, which may be affected by factors such as levels of compliance and persistence with treatment, or dose escalations or reductions. Costs used in this analysis were based on US WAC as of March 2017 and do not take into account factors such as rebates, coinsurance, copayments, and other cost-containment factors. Costs associated with administration, laboratory services, and treatment-related adverse events have also been excluded.

Conclusions

Ixekizumab consistently demonstrated greater efficacy than other FDA-approved biologics in the treatment of moderate-to-severe PsO. This is evident from the superior efficacy of ixekizumab relative to etanercept and ustekinumab in head-to-head clinical trials, and the higher efficacy, relative to placebo, of ixekizumab compared to all other evaluated biologics in this and other published NMAs across all levels of skin clearance, including secukinumab, ustekinumab, adalimumab, and etanercept.

Based on this analysis, ustekinumab 45 mg had the lowest monthly cost per additional PASI 75 responder, secukinumab 300 mg and ixekizumab 80 mg Q2W had the lowest monthly cost per additional PASI 90 responder, while ixekizumab had the lowest monthly cost per additional responder for achieving the highest level of clearance (i.e. PASI 100), compared with the other evaluated FDA-approved biologics in the treatment of moderate-to-severe PsO. Overall, based on this analysis, ixekizumab is considered the most cost-efficient biologic in the US when targeting complete resolution as measured by PASI 100 in PsO.

Transparency

Declaration of funding

The study was funded by Eli Lilly and Company.

Declaration of financial/other interests

SAS, SAF, RB, DA, AS, BZ, and SH are all full-time employees and stock holders of Eli Lilly and Company. CL has consulted for and/or been an Advisory Board Member for Abbvie, Amgen, Boehringer-Ingelheim, Dermira, Eli Lilly and Company, Janssen, Leo, Pfizer, Sandoz, and UCB and Vitae; has been an Investigator for Actavis, Abbvie, Amgen, Boehringer-Ingelheim, Celgene, Coherus, Cellceutix, Corrona, Dermira, Eli Lilly and Company, Galderma, Glenmark, Janssen, Leo Pharma, Merck, Novartis, Novella, Pfizer, Sandoz, Stiefel, Wyeth; and attended a Speaker’s bureau for Abbvie, Celgene, Novartis and Eli Lilly and Company.

Acknowledgments

The authors thank Sue Williamson and Caroline Spencer (Rx Communications, Mold, UK) for medical writing assistance during the preparation of this manuscript, which was funded by Eli Lilly and Company.