Retrophin, Inc.Corporate OverviewSummer 2015

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Forward-Looking Statements

This presentation contains forward-looking statements, including statements about our prospects,competitive position, regulatory filings and agency actions, and the anticipated development,timing, data readouts and therapeutic scope of programs in our clinical pipeline. These forward-looking statements may be accompanied by such words as “anticipate,” “believe,” “estimate,”“expect,” “forecast,” “intend,” “may,” “plan,” “project,” “target,” “will” and other words and termsof similar meaning. You should not place undue reliance on these statements.

These statements involve risks and uncertainties that could cause actual results to differmaterially from those reflected in such statements, including the safety and efficacy of ourproduct candidates, product competition, the occurrence of adverse safety events with ourproducts, adverse market and economic conditions, our dependence on collaborations and otherthird parties over which we may not always have full control, failure to comply with governmentregulation, our ability to protect our intellectual property rights, and have sufficient rights tomarket our products and services together with the cost of doing so, problems with ourmanufacturing processes and our reliance on third parties, our ability to attract and retainqualified personnel, our level of indebtedness, environmental risks, change of control provisionsin our collaborations and the other risks and uncertainties that are described in the Risk Factorssection of our most recent annual or quarterly report and in other reports we have filed with theSEC.

These statements are based on our current beliefs and expectations and speak only as of the dateof this presentation. We do not undertake any obligation to publicly update any forward-lookingstatements.

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Retrophin Overview

• Retrophin is a fully integrated biopharmaceutical company – Commercial platform of three products combined with a focus on discovery and

development of orphan drugs for the treatment of rare catastrophic diseases

• Significant revenue growth expected in 2015– Two of three commercial products expected to drive majority of top-line growth

Thiola® use for the treatment of cystinuria is expected to accelerate in 2015 after re-launching in late 2014

U.S. launch of Cholbam™ for the treatment of bile acid synthesis disorders is currently underway

• Multiple Research & Development candidates expected to drive substantial future value– Sparsentan expected to enroll last patient in Phase 2 DUET study by end 2015, followed

by potential subpart H filing– RE-024 Phase 1 underway, completion expected prior to year-end

• Unique Business Development capabilities will continue to drive shareholder value– Near-term accretive– Late-stage clinical/commercial rare disease assets

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Retrophin’s Pillars for Sustained Growth

Commercial Platform

• 725+ patients on Thiola therapy as of May 11, 2015, up ~12% from March 2015

• Adding new patients on a weekly basis

• Transitioning ~30 patients from clinical trial extension to commercial therapy

• New patients have been identified and begun Cholbam™ treatment

• Continued single digit patient growth

• Pursuing CTX indication for label

Rare Disease Research & Development

• Sparsentan

• Last patient expected to enroll in Phase 2 trial by end of 2015

• RE-024

• Phase 1 study underway

• Orphan & Fast Track designations granted in 2015

• RE-034

• Provisional patent application for novel formulation

• Discovery

• Additional rare disease targets

Aggressive Business Development

• Near-term accretive

• Rare-disease focus

• Minimal infrastructure needs

• Late-stage clinical

• Commercial

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Commercial Portfolio

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Thiola® (tiopronin)

• Trademark license and supply agreements with Mission Pharmacal for U.S. & Canadian markets

• Thiola® is an FDA approved small molecule for the prevention of cystine stone formation

– Binds with cystine to form a more soluble molecule which can be excreted in the urine

• Thiola® significantly reduces the number of stone events in patients with cystinuria

– Taken prophylactically

– If left untreated, cystinuria patients can have multiple stone events per year

2-months of cystine

stones formed by a

single teenage patient

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Cystine Stone Severity

• Small stones may be passed in urine however, medium stones often become lodged in the ureter creating a urinary obstruction

– Pressure from obstruction results in kidney damage, if left untreated can lead to chronic kidney disease

• Large stones may remain in the kidney and impair kidney outflow which can lead to severe infection

• Not a typical kidney stone

– Generally does not respond to lithotripsy

– Surgical intervention is regularly required to remove

Percutaneous Nephrolithotomy

• Pain comes without warning and can be debilitating to cystinuria patients

– Lifestyle revolves around stone formation - unable to travel, often miss work

– Surgery can lead to lengthy hospital visits and increased expense

An average of one surgical procedure every 3 years, with 7 surgical procedures by middle age1

Reference: 1.Barbey F, Joly D, Rieu P, et al. Medical treatment of cystinuria: critical reappraisal of long-term results. J Urol. May 2000;163(5):1419-23.

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Thiola® Efficacy

Naïve to

d-penicillamine

(n=14)

Previously treated

with d-penicillamine

(n=43)

Stone reduction

(reduced rate of new formation)94.1% 81.4%

Stone remission

(cessation of stone formation)71.4% 62.8%

References: 1. THIOLA® [prescribing information]. San Antonio, TX. Mission Pharmacal Company. 4. Biyani, et al. Medscape. http://emedicine.medscape.com/ article/435678-workup. Accessed August 11, 2014. Pak et. al. J. of Urology 0022-5347/86/1365-1003

In the renal proximal tubules in cystinuria With Thiola®

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Thiola® Market Opportunity

At least4,000 - 5,000candidates for Thiola®

~725+ patients on

therapy as of 5-11-15

~10,000 -

12,000 Stone-

Forming

Cystinuric

Patients in

U.S.*

• Improved Access

• Improved Support

• Improved Education

• Better Compliance

• Better Adherence

• More Prescribers

• Increased Patients

on Thiola®

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

Po

ten

tia

l T

hio

la C

an

did

ate

s

Thiola® candidate population is 6x

larger than current patient base

*Based on a subset of ~20,000 cystinuric patients in the U.S. as cited in: Knoll et al., Cystinuria in childhood and adolescence: recommendations for diagnosis, treatment, and follow-up, Pediatric Nephrology, 2005; 20:19-24

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Cholbam™ (cholic acid)

• Cholbam™ (cholic acid) is one of two primary bile acid therapies Oral dosing of 10 to 15 mg/kg/day

• First FDA approved treatment for pediatric and adult patients with bile acid synthesis disorders due to single enzyme defects and peroxisomaldisorders

Seven years of market exclusivity via orphan drug designation

• The absence of cholic acid in patients suffering from these disorders leads to:

Accumulation of potentially toxic bile acid intermediates in the liver (cholestasis) Malabsorption of fats and fat-soluble vitamins in the diet

• Treatment with Cholbam™ may: Prevent progression of liver disease Normalize liver biochemical and histological abnormalities

• If untreated, these patients fail to grow and may develop life-threatening liver injury, potentially resulting in liver transplant or death

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Cholbam™ Patient Population Dynamics

Overview

• Retrophin owns all rights and titles to Cholbam™

– Approximately 30 patients in clinical extension study

– 20+ patients have begun commercial therapy as of June 1, 2015

– New patients have been identified and begun therapy

Single Enzyme Defects

• Incidence of ~ 1 to 9 per million live births

– Many single-enzyme defect patients may live a prolonged life compared to absence of Cholbam™ therapy

PeroxisomalDisorders

• Incidence of ~ 1 in 50,000 live births

– Normally terminal conditions with a range of severity; majority of diagnosed patients do not live more than a few years

– Cholbam™ is considered an adjunctive therapy with the potential to treat the hepatic defects in peroxisomal disorders but it is not likely to prolong life for most of these patients

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Chenodal® (chenodeoxycholic acid)

• Chenodal® (CDCA) is a synthetic bile acid approved for the treatment of gallstones, but…

• …usage is exclusively in cerebrotendinous xanthomatosis (CTX)

– CDCA is the standard of care for CTX

– Chenodal® is the only FDA-approved formulation of CDCA

• Retrophin is seeking U.S. regulatory approval for the addition of the CTX indication to the Chenodal® label

– Met with the FDA in 1Q15, remain in discussions to determine an acceptable pathway for the addition of CTX to the label

– Chenodal® received Orphan Status for CTX in 2010 and could gain seven years of market exclusivity with changes to the current label

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Cerebrotendinous Xanthomatosis (CTX)

• CTX is very difficult to diagnose

– CTX patients begin life with refractory diarrhea, rarely leading to CTX diagnosis

– Disease progression then occurs with juvenile cataracts, tendon xanthomas (lipid deposition), and neurological deterioration (motor dysfunction, intellectual disabilities)

– Diagnosis generally occurs in patients in their mid-30’s after significant neurological damage

• The disease can be lethal without Chenodal® treatment

Age 30Age 20Age 10Birth

1 2 3 4 5 6 7 8 9 111213141516171819 212223242526272829 3132333435

Mean age at diagnosis 35.5 years1

(±11.8)

Reference: 1. Mignarri A, et al. J Inherit Metab Dis. 2014. ePub ahead of print. DOI 10.1007/s10545-013-9674-3.

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Earlier Diagnosis = Better Patient Outcomes

• Efforts are underway to educate pediatric ophthalmologists to raise awareness, facilitate earlier diagnosis, and improve patient outcomes

• Medical Science Liaisons (MSLs) in the field educating physicians

• Initiated prevalence study in April 2015

– Targeting 50 high-volume centers

– Goal of up to 500 patients screened

• Continue to expect a stable patient population with modest growth potential year over year until the impact of the outreach is known

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Business Development Focus

• Retrophin will continue to employ aggressive business development to complement the current operating structure

– Demonstrated ability to identify undervalued assets:

Thiola®

Chenodal®

Cholbam™

• A focused and disciplined screening approach covers the vast landscape of therapies approved during the modern era by the FDA

– Immediately eliminate non-strategic fits, resulting in higher quality idea generation and execution

– Opportunities are analyzed with the perspective of an equity investor, not solely a program manager

– Continuously analyzing numerous assets

• Proceeds of $245 million from the recent sale of a Rare Pediatric Disease Priority Review Voucher will enable Retrophin to act opportunistically and further develop current pipeline programs

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Development Portfolio

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Sparsentan for the Treatment ofFocal Segmental Glomerulosclerosis (FSGS)

• Disease where the glomeruli become progressively scarred and the kidney is dysfunctional

• There are up to 40,000 FSGS patients in the U.S.

• There are no FDA-approved treatments for FSGS

– Current standard of care: steroids, ACE/ARBs, calcineurin inhibitors, dialysis, and renal transplant

• Many FSGS patients will eventually progress to ESRD

– ~1,000 FSGS patients a year receive kidney transplants

References: Nephcure Kidney International FSGS Facts - http://nephcure.org/livingwithkidneydisease/understanding-fsgs/fsgs-facts/

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ARB: Established evidence of

protective effects in kidney and

cardiovascular system

ETA: Emerging evidence of

protective effects in kidney and

cardiovascular system

Sparsentan

AT1RETAR

Ang IIET 1

Dual action of Sparsentan

• Dual mechanism: Endothelin Type A (ETA) activity + ARB

• Sparsentan has a unique profile: strongly selective for Endothelin type A receptor (ETA) blockade combined with angiotensin blockade

Sparsentan – Dual Mechanism of Action

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Sparsentan Overview

• Endothelin Receptor Antagonist (ERA) + Angiotensin Receptor Blocker (ARB)

– ERAs are a $1B+ class

• Originally discovered by Bristol-Myers Squibb

– Initially developed for hypertension, with over 500 subjects in seven Phase 1 studies and two Phase 2 studies

– Phase 2 data reveals a well-tolerated drug

• Strong Intellectual Property

– Composition of Matter to 2019, with possible extension to 2024

• Granted orphan drug designation for treatment of FSGS in 2015

• Potential for accelerated approval under Subpart H if data are robust

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Sparsentan Phase II Study - DUET

• Largest FSGS study to be undertaken

– N=100

– 40+ U.S. and E.U. sites

– Last patient consented by year-end 2015

• Reduction in proteinuria at 8 weeks is primary endpoint

– Secondary endpoints: LDL reduction, Serum albumin, Weight change, Quality of life

• Randomized, double-blind vs. irbesartan

– Two week washout period

– 3:1 Sparsentan : active control

– Open-label extension

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Reducing Proteinuria Improves Renal Outcomes

• Reduction in proteinuria is the main treatment goal in many nephropathies

– Proteinuria damages the integrity of the glomerular filtration barrier by overloading renal tubules, causing an inflammatory and fibrotic cascade1

– Recent meta-analysis of interventional trials in both diabetic and non-diabetic CKD show a 30% reduction in proteinuria correlates to a 23.7% reduction in ESRD risk2

– Patients who have a reduction in proteinuria also demonstrate improved cholesterol, improved serum albumin, reduction in steroid dose and blood pressure improvement3

• Troyanov et al showed that FSGS patients who have a reduction in proteinuria have improved kidney survival4

– Complete Remission (CR) defined as proteinuria <0.3 g/d; 77% decrease in renal failure (p < 0.001) compared to NR

– Partial Remission (PR) defined as >50% reduction in peak proteinuria and to subnephrotic levels; 52% reduction in renal failure (p = 0.04) compared to NR

1Abbate, Zoja and Remuzzi, J Am Soc Nephrol 2006;17: 2974–29842Heerspink et al. J Am Soc Nephrol 2014; epub3Supavekin et al. Ped Int. 2012;54:793-7974Troyanov et al., J Am Soc Nephrol 2005; 16: 1061-1068

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RE-024 for the Treatment of Pantothenate Kinase-Associated Neurodegeneration (PKAN)

• Lethal, autosomal recessive neurodegenerative disorder

– Caused by mutations in PANK2, a kinase (gene discovered in 2001)

– Approximately 2,500 – 5,000 patients worldwide*

• Dystonia is the cardinal symptom of PKAN

– Classic (75%): childhood-onset, rapid progression form

Parkinsonian phenotype with loss of ambulation and early mortality due to disease complications and sequelae

– Atypical (25%): adult-onset, slower progression form

• No FDA/EMA approved treatments

*Source: NBIA Disorders Association

Image sources: NBIACure.org, http://perfecthealthdiet.com/2011/02/ketogenic-diet-for-nbia-neurodegeneration-with-brain-iron-accumulation/

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RE-024 and PKAN Biology

• Pantothenate kinase (Pank) phosphorylates pantothenate (PA) to yield phosphopantothenate (PPA)

• It is postulated that PANK2 deficient patients have decreased or no ability to synthesize PPA

• PPA is an essential precursor in the synthesis of Coenzyme A (CoA)

• CoA is important in many functions, mostly related to mitochondrial energy metabolism

• RE-024 is a phosphopantothenate replacement therapy

Pantothenate PhosphopantothenatePANK2

CoA

RE-024

several stepsX

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RE-024 Development

• Strong preclinical evidence

– RE-024 increases CoA levels in Pank KO mice and in Pank1 KO MEF and Pank2 silenced human neuroblastoma cells

• Four patients currently undergoing treatment via physician-initiated studies ex-U.S. in accordance with local laws and regulations

• Clearance of IND and initiated Phase 1 study underway

– Orphan & Fast Track designations granted in 2015

• Back-up compounds in development which have improved physicochemical properties and potency

RE-024 in Pank KO mice

WT

Ctr

l

KO

Ctr

lP

A

PP

A

RE

-024

0

1 0 0

2 0 0

3 0 0

4 0 0

Liv

er C

oA

pm

ol/

mg P < 0 .0 0 0 3

KO

Ctr

l

ME

F

Neu

roB

0

1

2

3

4

5

Co

A (

Fo

ld C

trl)

RE-024 in MEF and NB

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RE-034 (Synthetic ACTH)

• RE-034 is a synthetic ACTH analog (1-24 vs. 1-39) which is a pan-melanocortin receptor (MCR) agonist

– 1-24 ACTH preparations have shown similar clinical results to 1-39 preparations

• Physicians, patients, and regulators prefer synthetic medicines to animal-derived products

– The high cost of porcine ACTH has limited treatment access

• Filed for a provisional patent covering Retrophin’s novel formulation in 1Q15

• Currently exploring strategic options for development of RE-034

– Clinical studies could be initiated in 2016

– Clinical development strategy may include multiple severe rare disease indications

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Financials & Milestones

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Commercial Growth

• Net product sales grew 23% in the first quarter of 2015

• Cholbam™ will contribute to commercial growth starting in the second quarter of 2015

$27,900

$5.7mm

$8.3mm

$14.1mm

$17.4mm

$0

$3,000,000

$6,000,000

$9,000,000

$12,000,000

$15,000,000

$18,000,000

1Q14 2Q14 3Q14 4Q14 1Q15

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1Q15 Financial Overview

GAAP Reported Financials 1Q15 4Q14

Net Sales $17.4mm $14.1mm

Operating Expenses $25.2mm $33.6mm

Operating Income/(Loss) ($8.1mm) ($18.7mm)

Net Income/(Loss) $39.7mm ($29.0mm)

Cash and Marketable Securities $126.3mm $27.8mm

Non-GAAP Reported Financials 1Q15 4Q14

Operating Expenses $15.7mm $23.5mm

Operating Income/(Loss) $1.4mm ($8.6mm)

Net Income/(Loss) ($1.1mm) ($9.4mm)

Non-GAAP adjustments include: bargain purchase gain and resulting income tax benefit related to the Cholbam™ acquisition, change in fair

value of the Company’s derivative instruments, stock compensation, non-recurring legal expense, depreciation and amortization, finance

expense, and transaction & license fees

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Corporate Goals & Milestones

Significant top-line growth in 2015

Declining operating

expenses in 2015

Last patient consented in

sparsentan DUET trial by end 2015

&

Completion of RE-024 Phase 1

Study

Execution of at least one near-term accretive

transaction

30