 Cempra Corporate Presentation March 2012 Developing Well-Differentiated Antibiotics to Meet Medical Needs Exhibit 99.1 |
 Forward Looking Statement 2 This presentation contains forward-looking statements regarding future events. These statements are just predictions and are subject to risks and uncertainties that could cause the actual events or results to differ materially. These risks and uncertainties include, among others: risks related to the costs, timing, regulatory review and results of our studies and clinical trials; our ability to obtain FDA approval of our product candidates; our dependence on the success of Solithromycin and Taksta; our need to obtain additional funding and our ability to obtain future funding on acceptable terms; our anticipated capital expenditures and our estimates regarding our capital requirements; the possible impairment of, or inability to obtain, intellectual property rights and the costs of obtaining such rights from third parties; the unpredictability of the size of the markets for, and market acceptance of, any of our products, including Solithromycin and Taksta; our ability to produce and sell any approved products and the price we are able realize for those products; our ability to retain and hire necessary employees and to staff our operations appropriately; our ability to compete in our industry; innovation by our competitors; and our ability to stay abreast of and comply with new or modified laws and regulations that currently apply or become applicable to our business. Please refer to the documents that we file from time to time with the Securities and Exchange Commission. |
 Lead program, Solithromycin, has the potential to be the first Oral and IV macrolide approved since Zithromax/Z-PAK and is ready to begin Phase 3 trials in CABP Second program, Taksta, is an oral drug that is effective against MRSA, which we are developing for long-term treatment of Prosthetic Joint Infection (PJI), a potential orphan indication Large market opportunity with global antibiotic sales in the multibillions Significant need for new antibiotics driven by resistance and tolerability issues New FDA guidance provides clear regulatory pathway Strong management team with extensive successful experience in antibiotic drug development and approval - Azactam, Biaxin, Fidaxomicin, Synercid, Viread Highlights 3 |
 Significant need for new treatment driven by: Resistance Adverse events/lack of tolerability Inappropriate spectrum Lack of IV-oral Lack of pediatric dosing formulation Acceptability for long term use Developing Differentiated Antibiotics In a Large Market to Meet Significant Needs 4 Global antibiotics sales in 2009 Total $42B The growing need: At least 30% of pneumococci in the U.S. are resistant to azithromycin (Z-Pak) – the leading macrolide Growing need for oral therapies to address chronic Staph. aureus (MRSA) infections – chronic therapy of prosthetic joint infections |
 Cempra’s Portfolio Addresses The Critical Needs in The Antibiotic Market Non-Antibiotic Macrolide Program: GERD/Diabetic gastroparesis and COPD are in preclinical stage Product Formulation Preclinical Phase 1 Phase 2 Phase 3 CEM-101 (Solithromycin) Community Acquired Bacterial Pneumonia (CABP) Oral Intravenous (IV) Oral Suspension/Pediatric Future CEM-101 indications: Urethritis, Other respiratory tract infections (RTI’s), chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF), malaria, eye infections, etc. Oral – Urethritis Taksta™ Fusidic Acid Acute and Chronic Treatment of Staph (MRSA) Oral – Chronic Prosthetic Joint Infections Oral – ABSSSI Oral Suspension/Pediatric 5 |
 A next generation macrolide for respiratory tract infections, including CABP, entering Phase 3 6 Solithromycin – (CEM-101) |
 62.6% 25.5% 11.9% Extended Spectrum Macrolides Quinolones Other Solithromycin Opportunity 7 Azithromycin (Zithromax/Z-Pak), the leading macrolide, went generic in 2005 52 million prescriptions and $1.1 billion in sales in 2010 Widespread azithromycin use has led to resistance issues Lack of new macrolides with improved resistance profiles has led physicians to turn to fluoroquinolones (Levaquin) despite side effect concerns Total 2009 Pneumonia Oral Prescriptions – By Class (Branded and Generic) Source: IMS Macrolides are the most widely prescribed treatment for CABP and other RTIs Broad spectrum of activity Good safety Excellent tissue/intracellular distribution and anti-inflammatory activity Pneumococcal resistance rate in China – 96.4% Asian Network Surveillance: AAC. 2012, 56: 1418-1426 2 Canadian Bacterial Surveillance Network. http://microbiology.mtsinai.on.ca/research/cbsn/. Accessed March 2011 |
 Community-Acquired Bacterial Pneumonia (CABP) No. 1 cause of death due to infection Pneumococci is the most common cause of fatal CABP Most common cause of chronic bronchitis, sinusitis, meningitis and middle ear infection 5-6 million cases/year ~1 million hospital admissions/year ~1.6 million fatal cases of pneumococcal disease worldwide annually Pneumococcal diseases cause more deaths per year in U.S. than breast or prostate cancer Centers for Disease Control and Prevention. 2010. Active Bacterial Core Surveillance Report, Emerging Infections Program Network, Streptococcus pneumoniae, 2009. http://www.cdc.gov/abcs/reports- findings/survreports/spneu09.pdf. Accessed February 3, 2011. Xu. et al. Deaths: Final Data for 2007. Natl Vital Stat Rep. 2010; 58: 1-51 8 IDSA and KOLs recommend a -lactam plus a macrolide for CABP Several reports show that addition of a macrolide results in better patient outcome Addition of macrolide decreases mortality by >50% in patients with highest PORT scores |
 Community-Acquired Bacterial Pneumonia (CABP) – Standard-of-Care 9 Macrolides have kept a large segment of the global antibiotic market in spite of fluoroquinolones Macrolide segment not crowded Mostly occupied by azithromycin and clarithromycin – rising incidence of resistance No new macrolides except solithromycin Solithromycin is being developed for monotherapy for CABP - a cephalosporin would not be needed, eliminating side effects and costs of two drugs Solithromycin has the spectrum of activity that provides coverage for CABP pathogens, including azithromycin-resistant bacteria Step down IV to oral therapy could give a pharmacoeconomic advantage over current treatment options |
    History of Macrolide Development First Generation Macrolide Second Generation Macrolide In vitro activity is similar. Better PK, acid stable, fewer GI effects Third Generation Macrolides, “Ketolides” More potent than 2 nd generation macrolides Active against macrolide-resistant strains, 2 binding sites, acid stable, good PK, better tissue distribution Telithromycin – major adverse events Others have failed – no other new macrolides 10 Resistance is now widespread Fourth Generation Macrolide, Fluoroketolide More potent than 3 rd generation macrolides Active against 1 st , 2 nd and 3 rd generation macrolide-resistant strains, 3 binding sites, extended spectrum, good PK and tissue distribution, intravenous and oral dosing Effective in Phase 2 oral and well-tolerated |
 Ketek, a third generation macrolide, saw rapid uptake after approval Serious adverse events after approval Visual disturbance Myasthenia gravis Hepatotoxicity In 2006 FDA withdrew approval for all indications except for use in CABP No other macrolides have these issues Cempra research published in peer-reviewed article in Antimicrobial Agents and Chemotherapy Ketek, only macrolide to have a pyridine component Pyridine component inhibits nACh receptors in the liver, eye and muscle CEM-101 has been administered to over 220 subjects/patients and has been well-tolerated with none of the unusual side effects seen with Ketek Market needs remain after Ketek failure Ketek (Telithromycin) Failure Shows the Opportunity for Our New Macrolide 11 |
 # of Organisms Solithromycin Azithromycin MIC 90 (µg/ml) Strep. pneumoniae (150) 0.25 >16 Haemophilus influenzae (100) 2 2 Strep. pyogenes (100) 0.03 >16 Legionella pneumophila (30) 0.015 2 Mycoplasma pneumoniae (36) 0.000125 0.0005 Chlamydophila pneumoniae (10) 0.25 0.125 Solithromycin: Spectrum of Activity That Addresses CABP Pathogens Solithromycin (CEM-101) is several fold more potent than azithromycin against Strep. pneumoniae and Hemophilus influenzae, two critical pathogens in CABP 12 Solithromycin has demonstrated class-leading potency in vitro against macrolide-resistant pneumococcus CEM-101’s unique chemical structure necessitates mutations at three distinct sites for resistance to develop – no other macrolide has more than two |
 Population Solithromycin Levofloxacin Success rate, % Success rate, % ITT* 72.3 71.6 MITT 77.8 71.4 Solithromycin: Comparable Efficacy to Standard of Care (Levaquin) - Oral Phase 2 Trial 13 CEM-101 performed favorably in mITT at TOC when CABP pathogens were isolated - key criteria used by the FDA Randomized 132 patients received either Solithromycin or Levofloxacin: * Early Clinical Response defined as: Improvement at 72 hours in severity from baseline in at least two of the following signs/symptoms: cough, dyspnea, chest pain, sputum production Without worsening in any of the above 4 signs/symptoms - patient is clinically stable Proposed by FDA, November 3 rd 2011 for future CABP trial design and defined by the Foundation for the NIH (FNIH) |
 CEM-101 800/400 mg QD (N=64) Levofloxacin 750 mg QD (N=68) Any Treatment-Emergent Adverse Event (TEAE) 19 (29.7%) 31 (45.6%) Any study drug related TEAE 7 (10.9) 13 (19.1) Any Serious Adverse Event (SAE) 2* (3.1) 7** (10.3) Premature Discontinuation of Study Drug from adverse events 0 (0.0) 6 (8.8) Premature Discontinuation of Study Drug from study drug related adverse events 0 (0.0) 2 (2.9) Deaths 0 (0.0) 1 (1.5) Solithromycin: Favorable Safety and Tolerability in Phase 2 CEM-101 demonstrated a favorable safety and tolerability profile, with a lower incidence of treatment emergent adverse events than levofloxacin Fewer treatment emergent AEs (30% vs 46%) Fewer study subjects with SAEs (2 vs 7 subjects) Fewer drug discontinuations due to AEs (0 vs 6 subjects) Fewer GI related AEs (14% vs 24%) No liver safety or QT signals of concern, no bitter after-taste 14 *Both were unrelated to study drug **One was unrelated to study drug |
 Differentiation from Fluoroquinolones 15 Fluoroquinolones have a broad spectrum – but do not have Anti-inflammatory properties - lower mortality rates are noted when macrolides are added for CABP treatment Safety record of macrolides Use in pregnancy, pediatrics Resistance to fluoroquinolones is likely to increase with generic levofloxacin Fluoroquinolones affect bowel flora and select for CDAD Macrolides have less broad spectrum effects Fluoroquinolones can cause tendonitis and other side effects Avelox has QT effects Solithromycin when approved Could have the advantage of monotherapy in CABP Could be priced appropriately, and Could be noted to be fluoroquinolone sparing |
 Solithromycin: Intravenous Development First Injectable Macrolide in 20 Years 16 Intravenous macrolides have not been developed because of safety and tolerability issues FDA interest in intravenous - Allows enrollment of PORT III – IV patients Intravenous and oral formulation allow: Flexibility for treating severe or moderate pneumonia Severely ill patients begin treatment in the hospital and then go home earlier on oral therapy Pharmacoeconomic advantage IV toxicology, 28-day in dog and monkey was well-tolerated Phase 1 IV clinical trial underway |
 Plan for Phase 3 CABP Studies 17 Phase 3 CABP program consistent with the proposed FDA CABP guidance Nov. 2011: One oral trial Two IV-to-oral step-down trials Primary endpoint: Non-inferiority of early response (at 72 hours) compared to a fluoroquinolone Secondary endpoints: Safety and pooled mITT at early response Phase 3 oral planned to begin second half 2012 and complete in 2014 Global study – <50% PORT II, 50% PORT III and PORT IV Enroll ~800 patients Comparator moxifloxacin – a fluoroquinolone that is used worldwide at same dose Enrollment criteria controlled strictly as per FDA guidance Success criteria: as specified by newly proposed FDA guidance Safety and tolerability: secondary endpoints |
 18 Effective Macrolides Needed for CABP and Other Therapies A new macrolide is needed – for CABP because of resistance and mortality associated with treatment failures – no second chance upon failure Monotherapy and IV-Oral could allow pricing and efficacy advantage over combination of -lactam, such as a cephalosporin, plus macrolide which is the standard of care Secondary studies in pharyngitis planned to be run against azithromycin to show superiority- high resistance rates makes this possible Solithromycin could have intravenous advantage, has good oral bioavailability and could have better anti-inflammatory properties than any other macrolide |
 19 Solithromycin for CABP and Multiple Indications – Potential Broad Use Solithromycin- The Next Generation Macrolide- First Fluoroketolide Campylobacter diarrhea Helicobacter gastritis Gonococcal and Non- Gonococcal Urethritis Simple skin infections Group B Strep infections in pregnancy Lyme disease and other tick borne diseases Other Diseases: Ophthalmic drops Pediatric infections Malaria Prophylaxis Biodefense GI Tract Diseases: Antibacterial and Anti- inflammatory: Primary Indication : CABP Simple RTI’s, Pharyngitis, Sinusitis, Bronchitis, Acute Exacerbation of Chronic Bronchitis (AECB) GU Tract Diseases: Respiratory Tract Infections (RTI): COPD Cystic fibrosis Panbronchiolitis |
 20 TAKSTA™ (Fusidic acid) An oral antibiotic for MRSA infections being developed for chronic use in the U.S. |
 21 What is Taksta TM ? Taksta is Cempra’s proprietary fusidic acid dosing regimen Fusidic acid approved in Western Europe, Australia, and other countries 40 years of established safety and efficacy profile in acute and chronic use in staph infections ex-U.S. NCE in the US, Hatch Waxman exclusivity obtained by Cempra, dosing regimen patent, supply agreement of drug substance - a fermentation product Unique structure, no-cross resistance with any other antibiotic Orally bioavailable Targeted against Gram-positive pathogens, including MRSA - a pathogen of great concern |
   Antimicrobial agents MIC (µg/ml) 90% % susceptible Fusidic acid 0.12 99.6 Clindamycin >2 69.7 Erythromycin >4 11.2 Levofloxacin >4 30.2 Linezolid 1 99.9 Tetracycline 1 95.8 TMP/SMX 0.5 97.9 Compared with other Oral Agents Compared with other Oral Agents Tetracyclines and Bactrim (TMP/SMX) have significant limitations for oral, outpatient use Linezolid is the only oral antibiotic approved for MRSA but is not recommended for long term use TAKSTA has Excellent Activity Against S. aureus in the U.S. (1,710 U.S. strains) 22 Taksta is highly effective against S. aureus strains found in the U.S. Almost all staph and MRSA in the U.S. are susceptible |
 23 Osteomyelitis/Prosthetic Joint Infection is a Significant Opportunity Growing need for oral therapies to address MRSA infections Physicians cite staph (MRSA) as top pathogen of concern in prosthetic joint infections and osteomyelitis Prosthetic joint replacement is increasing Risk of life-long bacterial infection of implant Minimum duration of treatment is 4-6 weeks, with many patients requiring life-long treatment Leading drugs for prosthetic joint infections and osteomyelitis are the same as those for ABSSSI: vancomycin, daptomycin and linezolid Total prosthetic-joint infections 1990-2004 (Kurtz et. al) New England J Medicine, 2009 Total arthroplasties performed from 1990-2006 (CDC) |
 European dosing Cempra’s loading dose 1500 BID loading dose followed by 600 mg maintenance dose – minimizes resistance development Loading dose regimen validated – resistance not noted in Phase 2 study Patent pending Cempra’s Proprietary TAKSTA Loading Dose Validated - Phase 2 Study With MRSA Infections Cempra developed a proprietary loading dose regimen to prevent resistance to fusidic acid that has occurred outside the U.S. 24 Data from 155-patient Phase 2 trial demonstrates efficacy and safety in ABSSSI Comparable efficacy to Zyvox (linezolid) Proprietary loading dose regimen was well tolerated and overcame resistance Comparable safety to linezolid, despite trial design excluding patients for whom linezolid is contra- indicated (e.g., those on SSRIs) End of Phase 2 meeting for ABSSSI with FDA completed |
  Use In Prosthetic Joint Infections 25 Used outside the U.S. in Osteomyelitis/PJI Significant physician interest for chronic use in the U.S. Eur J. Clin Microbiol Infect Dis (2010) 29: 171-180 Several reports from ex-USA that PJI can be successfully treated by adding FA to the standard of care Taksta could address the need for a safe, oral product for acute and chronic treatment in prosthetic joint infections |
    Safety Tedizolid Tedizolid Linezolid Linezolid Taksta Taksta 26 Two compassionate use cases of bone/prosthesis infections in North America Efficacy is comparable to linezolid but has better safety – useful for oral chronic use in all patient populations PJI Facts: 200K Hip Replacements; 550K Knee Replacements in 2007 Surgeries increase by 3% per year 1% of hips and 2% of knees develop PJI's Chronic daily therapy Potential for Taksta for Chronic Use in Prosthetic Joint Device Infections |
 Current Treatment: Debride and treat intravenously and orally for months – replace prosthesis if possible – may not be possible in older patients Study Design: Success Criteria: The primary outcome – retention of a functional prosthesis at the end of 3 months Other outcome measures: longer term safety and tolerability, joint & mobility function Cempra will confirm trial design with the FDA – Orphan indication potential 27 Prosthetic Joint Infection Phase 2 Trial Plan – Chronic Oral Treatment of MRSA 50 patients with Knee or Hip PJI Patient Population IV vancomycin + Taksta + Rifampin Discontinue vancomycin at 7-28 days Add Taksta to Current Standad of Care Continue with Taksta + Rifampin for 3 months Continue for 3 Months Taksta as oral monotherapy beyond 3 months Long-Term Therapy |
  2012 Milestones 2Q 12: CEM-101 End of Phase 2 review of Oral Phase 3 protocol 2H 12: CEM-101 Initiation of Phase 3 Oral Trial for CABP 2H 12: CEM-101 Completion of Phase 1 IV 4Q 12: Taksta Initiation of Phase 2 Prosthetic Joint Infection Trial 4Q 12 Solithromycin top line data of Phase 2 Gonococcal Urethritis Study 2013 Milestones 1H 13: CEM-101 Initiation of First Phase 3 IV-to-Oral CABP Trial (with partner funding) 2H 13: CEM-101 Initiation of Second Phase 3 IV-to-Oral Trial (with partner funding) 4Q 13: Taksta top line Prosthetic Joint Infection results 2014 Milestones 1H 14: Taksta Phase 2 Prosthetic Joint Study Results 1H 14: CEM-101 Phase 3 Oral CABP Top line data 28 Clinical Development Plan and Milestones |
 Capitalization 29 Cash & Equivalents (at 9/30/11) * $ 9M Long-Term Debt (at 9/30/11) $ 5M Shares Outstanding 21.0M Market Capitalization (at 2/28/12) $160.2M Cash Runway ** 1H 2014 * Does not include proceeds of 12/11 $10M venture debt or 2/12 $57.9M IPO ** Includes initiation of CEM-101 P3 oral trial and Taksta P2 PJI trial; Does not include any potential partnerships. |
 Kenneth Touw, PhD EVP Regulatory Carl Foster EVP Business Development Mark Hahn, CPA CFO David Oldach, MD SVP Clinical GILEAD Prabhavathi Fernandes, PhD President & CEO Proven Management Team David Pereira, PhD SVP Chemistry • Azactam (aztreonam) • Biaxin (clarithromycin) • Dificid (fidaxomicin) • Plenaxis (abarelix) • Zavesca (miglustat) • OncoVax • Prilosec (omeprazole) • IPO and M&A • Athenix-Bayer CropScience • Charles & Colvard (CTHR) • E&Y • Viread • GS-9190 • Combinations against HCV • Synercid (quinupristin/ dalfopristin) • Altace (ramipril) • Embeda (morphine and naltrexone) • Acurox (oxycodone) • Injectable Penicillins • Dobutamine HCl Injection • Ranitidine Injection 30 |