Lassa Virus Therapeutics and Target Product Profile

Sina Bavari, Ph.D. US Army Medical Research Institute of

Infectious Diseases (USAMRIID) Frederick, MD

sina.bavari.civ@mail.mil

Objectives:

1) How to identify and evaluate potential therapeutics 2) Current bench research and clinical grade “therapeutics"

4) Ideal therapeutics for emerging pathogens under difficult situation

4) Target Product Profile for therapeutic use of drugs agisnt Lassa Fever Virus

Lassa Fever Virus Target Product Profile

This presentation will not cover IPEP, PEP, or other prophylaxis types of use.

Therapeutic Targets for high consequence Viruses

Viral proteins: Coronaviruses (S protein) Arenaviruses (GP1, GP2) Paramyxoviruses (G, F proteins) Bunyaviruses (Gn, Gc proteins) Cellular receptors: Coronaviruses (DPP4) Paramyxoviruses (ephrin-B2/-B3) Arenaviruses (multiple)

RNA polymerase (Bunya, Arena, Paramyxo)

Abs

Fusion/ entry

inhibitors

Protease inhibitors

Nucleoside analogs

Assembly inhibitors Host modulators/ immunomodulators

Egress inhibitors

Arenaviruses (Z protein) Paramyxoviruses (M protein) Bunyaviruses (RVFV)

Paramyxoviruses (M protein) Bunyaviruses (SKI-1)

Viral proteases: Coronaviruses (3CLpro, PLpro) Cellular proteases: Coronaviruses (cathepsins B, L, TMPRSS2) Arenaviruses (SKI-1)

Bunyaviruses (RVFV) Arenaviruses (GP2) Paramyxoviruses (F protein) Coronaviruses (S protein)

Proteasome inhibitors

Bunyaviruses (RVFV)

Kinase inhibitors

Bunyaviruses (RVFV) Arenaviruses (LASV)

Bunyaviruses Coronaviruses

From Campbell Biology: Concepts & Connections (5th ed)

High Content Imaging Assay for Viral Infection

1. Cell Plating

2. Compound Treatment

3. Virus Dispensing

4. Immuno-fluorescence Staining

DRAQ5 anti-Virus IgG-Alexa488

5. Confocal High Throughput Imaging

6. Image Analysis Nuclei Cytoplasm Pathogen Pos. Cells

7. Multi-parametric Data Analysis

PE Janus MDT

PE Opera

BSL2,3,4

20 hrs

2 hrs

48 hrs

+24hrs

GeneData Screener and PE SpotFire

Veronica Soloveva, , 8 April 2018

5

Therapeutic evaluation of compounds against viral infection

EC50, uM

HCI 0.215

Plaque assay 0.145

RT-PCR 0.172

[Inhibitor ] DMSO (+ control)

No infection (- control)

Viral infection of HeLa Cells

-9 -8 -7 -6 -5

-2 5

0

2 5

5 0

7 5

1 0 0

lo g M

% I

nh

ibit

ion

HCI

P laque

RT-PCR

N=2

% In

hib

itio

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Log Concentration [M]

Veronica Soloveva, , 8 April 2018

Antivirals Host-response modifiers

Potential Lassa Virus Therapeutics

Potential Lassa Virus Therapeutics

Antivirals

Biologics

NA-based

Small Molecule non-Nucs (LHF-535)

Small Molecule Nucs (T-705) Blood product

mAbs

IFNab

SiRNA PMO

Synthetic

Ideal therapeutics for emerging infections

1) Easy to access, easy to store, and widely available 2) Inexpensive 3) Safety/safety/safety 4) Easy to administer 5) Long-shelf life 6) Clear uncomplicated regulatory path for approval 7) Broad activity against multiple families of viruses 8) Treat/intervene at any stages of infection 9) Can be added to other treatment options 10)Well distributed to multiple tissues based on the infection pattern

Therapeutics: Lassa Virus

Compound Mechanism Stage Notes

Ribavirin Nucleoside analog Approved in humans Some effect if administered early; Tx

efficacy needs to be formally investigated.

Favipiravir Nucleobase In vivo efficacy –small

animals Synergistic effect in combination with

Ribavirin?

ST-193 Entry inhibitor In vivo efficacy – guinea pigs Inhibits pH-induced membrane fusion

Genistein , many others

Entry inhibitor/host modulator/replication

In vitro data EC50 nM-uM Isoflavone; kinase inhibitor/Nuc

LHF-535 Entry inhibitor Finishing Pre-clinical Kineta/Wellcome Trust

Finishing pre-IND studies

huMAbs Antiviral In vivo efficacy – guinea

pigs/NHPs May not be consistent with TPP (cost,

manufacturing, etc)

IFN-alfacon-1 Immune modulator Approved in humans IFN consensus; combination with

Ribavirin or other antivirals

Clinical disease: • Ranges from mild flu-like illness to severe hemorrhagic fever • Deafness is a sequelae in some survivors Therapeutic strategies: • Difficult to target entry – different arenaviruses use different cellular receptors; • Target cell processes critical for entry and replication (e.g. kinase inhibitors)

LASV Therapeutic (Reactive/Emergency Use) TPP (Preliminary Draft Apr 2018)

Category Threshold Optimal

Patient Population Adults (18-62 years), excluding pregnant

& lactating women

Children, Adults, Geriatrics (2-62+ years),

suitable for pregnant & lactating women

Safety 42d - 3mo: Regulated NHP safety or

other appropriate models

Human safety evaluated: NHV/patients

(<50 subjects)

Tolerability No critical or severe adverse events;

tolerable AEs acceptable (eg: rash, GI)

Well tolerated, transient, manageable

AEs

- No drug-drug interactions

- Acceptable for use in pregnant women

Efficacy

Effective vs various LASV (Broad Spectrum/outbreak strain), 2-log reduction viremia in serum , Decrease clinical signs by 50%, Survival benefit >50%

Effective vs ≥ 2 arenaviruses (current outbreak strain and or other AVs) , 3-log reduction viremia in serum, Decrease clinical signs by 80%, Survival benefit >80%

Route of Administration Parenteral (IV/IM/subcutaneous) Oral and parenteral

Frequency of Dosing Continuous infusion or TID QD or BID

Duration of Treatment 21 days 10-14 days

Onset of Action Efficacy <24hr after confirmed infection Efficacy >24hr after confirmed infection

Storage Condition 2-8oC 20oC – 35oC

Shelf Life 2 years (cold chain acceptable) 5 years (room temperature)

Manufacturing/Stock-

pilling Synthesis (100-1,000) treatments)

Efficient, high yield synthesis (1,000-Ms

treatments)

Cost of Goods Affordable in limited healthcare areas

$10-20 Global deployment opportunity $1-5

Patient Population

Safety

Tolerability

Efficacy

Route of Administration

Frequency of Dosing

Duration of Treatment

Onset of Action

Storage Condition

Shelf Life

Manufacturing/Stock-pilling

Cost of Goods

Patient

Population

Adults (18-62 years),

excluding pregnant &

lactating women

Children, Adults, Geriatrics

(2-62+ years), suitable for

pregnant & lactating

women

Safety

42d - 3mo: Regulated NHP

safety or other

appropriate models

Human safety evaluated:

NHV/patients (<50

subjects)

Tolerability

No critical or severe

adverse events; tolerable

AEs acceptable (eg: rash,

GI)

Well tolerated, transient,

manageable AEs

- No drug-drug interactions

- Acceptable for use in

pregnant women

Category Threshold Optimal

Lassa Virus Therapeutics: Target Product Profile

Efficacy

Effective vs various LASV Broad Spectrum/outbreak strain), 2-log reduction viremia in serum , Decrease clinical signs by 50%, Survival benefit >50%

Effective vs ≥ 2 arenaviruses (current outbreak strain and or other AVs) , 3-log reduction viremia in serum, Decrease clinical signs by 80%, Survival benefit >80%

Route of

Administration

Parenteral

(IV/IM/subcutaneous) Oral and parenteral

Frequency of

Dosing

Continuous infusion or

TID QD or BID

Duration of

Treatment 21 days 10-14 days

Category Threshold Optimal

Lassa Virus Therapeutics: Target Product Profile

Onset of Action Efficacy <24hr after

confirmed infection

Efficacy >24hr after

confirmed infection

Storage

Condition 2-8oC 20oC – 35oC

Shelf Life 2 years (cold chain 2-8oC

acceptable)

5 years (room

temperature)

Manufacturing/

Stock-pilling

Synthesis (100s-1,000)

treatments)

Efficient, high yield

synthesis (more than

1,000-treatments)

Cost of Goods Affordable in limited

healthcare areas $10-20

Global deployment

opportunity $1-5

Category Threshold Optimal

Lassa Virus Therapeutics: Target Product Profile